In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Example input: what is the first event mentioned?, Context: The Russian Revolution is the series of revolutions in Russia in 1917, which destroyed the Tsarist autocracy and led to the creation of the Soviet Union. Following the abdication of Nicholas II of Russia, the Russian Provisional Government was established. In October 1917, a red faction revolution occurred in which the Red Guard, armed groups of workers and deserting soldiers directed by the Bolshevik Party, seized control of Saint Petersburg (then known as Petrograd) and began an immediate armed takeover of cities and villages throughout the former Russian Empire.
Example output: Russian Revolution
Example explanation: This is a good example, and the Russian Revolution is the first event mentioned.
Q: What necessitated Germany's alliance with the Soviet Union?, Context: For Germany, because an autarkic economic approach or an alliance with Britain were impossible, closer relations with the Soviet Union to obtain raw materials became necessary, if not just for economic reasons alone. Moreover, an expected British blockade in the event of war would create massive shortages for Germany in a number of key raw materials. After the Munich agreement, the resulting increase in German military supply needs and Soviet demands for military machinery, talks between the two countries occurred from late 1938 to March 1939. The third Soviet Five Year Plan required new infusions of technology and industrial equipment.[clarification needed] German war planners had estimated serious shortfalls of raw materials if Germany entered a war without Soviet supply.
A:
an autarkic economic approach or an alliance with Britain were impossible