Explanation: The source indicates that Hitler ordered the invasion following the Yugoslav coup d'état of March 27, 1941, which overthrew the government that had adhered to the Tripartite Pact. The coup, not the adherence itself, was the direct trigger.

Explanation: On March 25, 1941, the Yugoslav government, led by Regent Prince Paul, signed the Tripartite Pact, thereby aligning the Kingdom of Yugoslavia with the Axis powers.

Explanation: The coup d'état of March 27, 1941, which overthrew the pro-Axis government, angered Adolf Hitler and led him to order the 'military destruction' of Yugoslavia, indicating a highly unfavorable German reaction.

Explanation: Adolf Hitler ordered the invasion of Yugoslavia on March 27, 1941, directly in response to a coup d'état that overthrew the government which had recently adhered to the Tripartite Pact.

Explanation: On March 25, 1941, Yugoslavia acceded to the Tripartite Pact, signifying its alignment with the Axis powers under Regent Prince Paul's government.

Explanation: Adolf Hitler reacted with extreme anger to the Yugoslav coup d'état of March 27, 1941, issuing Führer Directive No. 25 which mandated the 'military destruction' of Yugoslavia.

Explanation: The primary codename for the German invasion of Yugoslavia was 'Operation 25'. 'Operation Barbarossa' was the codename for the German invasion of the Soviet Union.

Explanation: German ground forces launched attacks into Yugoslavia from multiple directions, including bases within Germany itself, as well as from Romania, Hungary, and Bulgaria.

Explanation: The German invasion force comprised approximately 19 divisions, including five panzer divisions, two motorized infantry divisions, and two mountain divisions, supported by over 750 aircraft.

Explanation: The main Axis ground offensive commenced on April 6, 1941, with German forces, and was joined by Italian and Hungarian forces on April 11, 1941, well before the armistice on April 17, 1941.

Explanation: The codename 'Spring Storm' (*Frühlingssturm*) referred to the location of Adolf Hitler's special command trains, 'Amerika' and 'Atlas,' which were stationed in Austria during the April War.

Explanation: The primary codename for the German invasion of Yugoslavia, launched on April 6, 1941, was 'Operation 25'.

Explanation: German ground forces launched attacks into Yugoslavia from multiple directions, including bases within Germany itself, as well as from Romania, Hungary, and Bulgaria.

Explanation: The German invasion force comprised approximately 19 divisions, including five panzer divisions, two motorized infantry divisions, and two mountain divisions.

Explanation: The invasion of Yugoslavia was primarily carried out by Germany, Italy, and Hungary, with Romania and Bulgaria also playing supporting roles or allowing passage.

Explanation: Initially, Italian forces limited their involvement to air and artillery attacks. The major Italian ground offensives into Yugoslavia commenced on April 11, 1941.

Explanation: Hungary, having joined the Tripartite Pact, mobilized its army and crossed into Yugoslav territory on April 11, 1941, advancing into the Bačka and Baranya regions with minimal resistance.

Explanation: Italian naval forces occupied Dalmatian islands and supported ground advances along the coast. They also conducted air raids on Yugoslav naval assets and damaged Yugoslav vessels, indicating a role beyond mere blockade.

Explanation: Contrary to opposing it, Hungarian Chief of Staff Henrik Werth was a key proponent and planner of Hungary's participation in the invasion, meeting with German officials to finalize operational plans.

Explanation: While Romania allowed German forces to stage from its territory and provided some artillery support along the Danube, it did not provide significant ground troop support for the invasion itself.

Explanation: Italian intelligence services achieved success in breaking Yugoslav codes and subsequently transmitted deceptive orders using the correct code key, causing significant confusion and disruption to Yugoslav troop movements.

Explanation: In addition to Germany, the invasion of Yugoslavia involved significant participation from Italy and Hungary, both members of the Axis powers.

Explanation: Initially limited to air and artillery actions, the Italian Army launched its major ground offensives into Yugoslav territory on April 11, 1941.

Explanation: Following Hungary's mobilization and border crossing on April 11, 1941, its forces advanced into the Bačka and Baranya regions of Yugoslavia.

Explanation: The Royal Yugoslav Army was only partially mobilized and heavily reliant on animal-powered transport. While it possessed some modern equipment, its overall armament and readiness were not comparable to German forces.

Explanation: The Royal Yugoslav Air Force operated a mix of aircraft, including modern fighters like the Messerschmitt Bf 109 and Hawker Hurricane, alongside older types. It was not solely equipped with outdated biplanes.

Explanation: The Royal Yugoslav Navy was relatively small, primarily consisting of four destroyers and four submarines, along with some river monitors and motor torpedo boats. It did not possess battleships or aircraft carriers.

Explanation: Deep political divisions within Yugoslavia, notably between Serbs and Croats, undermined the cohesion and effectiveness of the Yugoslav Army's defense, with some units reportedly unwilling to fight or even mutinying.

Explanation: While many aircraft were lost, a significant number of surviving Royal Yugoslav Air Force aircraft escaped to Allied territory or were destroyed later, rather than most being destroyed solely on the ground during the initial invasion.

Explanation: A significant strategic error cited for the Yugoslav Army's rapid collapse was its attempt to defend all national borders concurrently, stretching its resources and command capabilities too thin.

Explanation: The Royal Yugoslav Army was only partially mobilized and relied significantly on animal-powered transport, indicating a lack of modern mechanized capabilities compared to the invading Axis forces.

Explanation: The core strength of the Royal Yugoslav Navy consisted of four destroyers and four submarines, supplemented by smaller vessels like motor torpedo boats and river monitors.

Explanation: The rapid collapse of the Royal Yugoslav Army was significantly influenced by the strategic error of attempting to defend all borders simultaneously and the exacerbating effect of internal political divisions, particularly between Serbs and Croats.

Explanation: Many of the Yugoslav aircraft that successfully escaped the invasion and reached Allied territory were subsequently integrated into Allied air forces or were lost due to combat or attrition.

Explanation: The Luftwaffe initiated the invasion on April 6, 1941, with a massive air attack on Belgrade, codenamed 'Operation Retribution' (Unternehmen Strafgericht).

Explanation: The air raids on Belgrade virtually destroyed the capital's communication systems, severely hampering the ability of the Yugoslav high command to coordinate with its forces in the field.

Explanation: Despite achieving some aerial victories, the Royal Yugoslav Air Force suffered significant losses during its defense against the initial Luftwaffe attacks on April 6th and 7th.

Explanation: The Yugoslav offensive in Albania was hampered by the rapid German advance and the fall of Skopje, failing to achieve its strategic objectives and thus not significantly aiding the overall Yugoslav defense.

Explanation: The four Yugoslav river monitors were scuttled by their crews on April 12, 1941, to prevent their capture by advancing Axis forces, rather than being captured intact.

Explanation: Fritz Klingenberg, a German captain, secured Belgrade's surrender through deception and bluff, not a large military display. He convinced the mayor that a significant German force was present and ready to bombard the city.

Explanation: The city of Niš was strategically vital as a key point for breaking Yugoslav defenses and enabling the Axis advance towards Belgrade, making it a crucial objective for both sides.

Explanation: The Yugoslav destroyer *Zagreb* was deliberately scuttled by its own crew at Kotor to prevent its capture by Axis forces, rather than being captured intact.

Explanation: The Yugoslav offensive in Albania was not successful and was hampered by the German advance. Furthermore, the source does not indicate that superior Yugoslav naval support was a factor in its outcome.

Explanation: The Yugoslav destroyer *Beograd* was damaged by Italian aircraft off Šibenik, but the source does not state it was sunk by Italian naval forces during the invasion.

Explanation: The Yugoslav Supreme Command did deploy strategic reserves, such as the 2nd Cavalry Division, to bolster defenses, including those around Niš. However, these units faced harassment from the Luftwaffe during transit.

Explanation: The Luftwaffe's initial and devastating air campaign against Belgrade, commencing on April 6, 1941, was codenamed 'Unternehmen Strafgericht,' which translates to 'Operation Retribution'.

Explanation: The extensive air raids on Belgrade caused severe damage to the city's communication infrastructure, critically disrupting the Yugoslav high command's ability to coordinate military operations.

Explanation: Despite facing overwhelming odds, the Royal Yugoslav Air Force fighter squadrons engaged the Luftwaffe on April 6th and 7th, achieving notable aerial victories, albeit at a significant cost to their own strength.

Explanation: The Yugoslav offensive in Albania, intended to support a strategic withdrawal, was ultimately hampered by the rapid German advance and the fall of Skopje, preventing it from achieving its strategic objectives.

Explanation: To prevent its capture by Axis forces, the Yugoslav destroyer *Zagreb* was deliberately scuttled by two junior officers at Kotor, rather than surrendering or being destroyed by enemy action.

Explanation: Fritz Klingenberg, a German captain, played a crucial role in the swift capture of Belgrade by bluffing the city's mayor into believing a large German force was present and ready to attack, thus securing an early surrender.

Explanation: The city of Niš was strategically vital as a key point for breaking Yugoslav defenses and enabling the Axis advance towards Belgrade, making it a crucial objective for both sides.

Explanation: After enduring repeated attacks from German dive-bombers, the remaining Yugoslav river monitors were scuttled by their crews on April 12, 1941, to prevent their capture by advancing Axis forces.

Explanation: After the invasion and partition by the Axis powers, Croatia was established as the Independent State of Croatia (NDH), a puppet state aligned with Germany and Italy.

Explanation: While a large number of prisoners were taken, the combined total captured by German and Italian forces was between approximately 284,000 and 375,000, not over 500,000.

Explanation: The armistice was signed on April 17, 1941, and came into effect at noon on April 18, 1941, marking the unconditional surrender of the Yugoslav Army after just eleven days of fighting.

Explanation: During the evacuation of the Yugoslav government, the nation's gold reserves were airlifted to Greece using surviving aircraft, including Dornier Do 17Ks.

Explanation: The swift military defeat and subsequent occupation and partition by the Axis powers resulted in the dissolution of the Kingdom of Yugoslavia as a sovereign entity.

Explanation: Following the Yugoslav Army's surrender, Colonel Draža Mihailović promptly initiated the organization of resistance forces in the mountainous regions of Serbia and Eastern Bosnia.

Explanation: The Independent State of Croatia (NDH) was established as a puppet state, heavily influenced and controlled by the Axis powers, primarily Germany and Italy, rather than being truly independent.

Explanation: The occupation and partition of Yugoslavia following the invasion directly contributed to the emergence and growth of significant resistance movements, including the Yugoslav Partisans and the Chetniks.

Explanation: During the invasion, local uprisings and proclamations of independence occurred in various regions, including the declaration of the Independent State of Croatia in Bjelovar and Ustaša actions in Mostar.

Explanation: Following the invasion, Yugoslavia was occupied and partitioned by the Axis powers. Territories were annexed by Germany, Italy, Hungary, and Bulgaria, and Croatia was established as the Independent State of Croatia (NDH), a puppet regime.

Explanation: The Axis powers captured a substantial number of Yugoslav prisoners of war, with estimates ranging between approximately 284,000 and 375,000 soldiers.

Explanation: The armistice, signifying the unconditional surrender of the Yugoslav Army, officially came into effect at noon on April 18, 1941, concluding the invasion after eleven days.

Explanation: The Yugoslav gold reserves were evacuated to Greece by air, utilizing surviving aircraft such as Dornier Do 17Ks and other transport planes during the government's flight.

Explanation: The statement 'Montenegro (as an independent state)' is false. Following the partition, Italy annexed territories along the Adriatic coast, which included Montenegro. Therefore, Montenegro was not an independent state but was directly controlled by an Axis power.