Given the task definition, example input & output, solve the new input case.
In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.
Example: Question: When did the operation during which the 704th dropped supplies to allied troops near Nijmegen begin? Passage: The group was occasionally diverted from strategic missions to carry out air support and interdiction missions. It supported Operation Overlord, the invasion of Normandy by attacking transportation targets, including bridges, along with airfields and strong points in France. On D Day, the squadron and the rest of the 446th Group led the first heavy bomber mission of the day. The 446th aided ground forces at Caen and Saint-Loduring July by hitting bridges, gun batteries, and enemy troops. During Operation Market Garden, the attempt to seize a bridgehead across the Rhine in the Netherlands, the 704th dropped supplies to allied troops near Nijmegen. It struck lines of communications during the Battle of the Bulge. During Operation Varsity in March 1945, it supplied ground and airborne troops near Wesel. The squadron flew its last combat mission on 25 April 1945 against Salzburg, Austria. The group had flown 273 missions and had lost 58 aircraft during the war,
. Links: a. Allies of World War II b. Wesel c. Operation Market Garden d. Air Support.
Output: c
The passage describes the 704th's actions during Operation Market Garden.

New input case for you: Question: Approximately how many people died in the massacares at the end of the Russian Revolution? Passage:During the Russian Revolution of 1905, conflict erupted between the Armenians and the Azeris, culminating in the Armenian-Tatar massacres. In the final year of World War I, Nakhchivan was the scene of more bloodshed between Armenians and Azerbaijanis, who both laid claim to the area. By 1914, the Armenian population was at 40% while the Azeri population increased to roughly 60%. After the February Revolution, the region was under the authority of the Special Transcaucasian Committee of the Russian Provisional Government and subsequently of the short-lived Transcaucasian Democratic Federative Republic. When the TDFR was dissolved in May 1918, Nakhchivan, Nagorno-Karabakh, Zangezur (today the Armenian province of Syunik), and Qazakh were heavily contested between the newly formed and short-lived states of the First Republic of Armenia and the Azerbaijan Democratic Republic (ADR). In June 1918, the region came under Ottoman occupation. Under the terms of the Armistice of Mudros, the Ottomans agreed to pull their troops out of the Transcaucasus to make way for the forthcoming British military presence.
Links: a. ArmenianTatar massacres of 190507 b. Armistice of Mudros c. Russian Provisional Government d. Syunik Province
Output:
a