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.

Input: Consider Input: Question: How many species of the Aru Flying fox are there? Passage:Of the 62 flying fox species evaluated by the IUCN as of 2018, 3 are considered critically endangered: the Aru flying fox, Livingstone's fruit bat, and the Vanikoro flying fox. Another 7 species are listed as endangered; 20 are listed as vulnerable, 6 as near threatened, 14 as least concern, and 8 as data deficient. A further 4 are listed as extinct: the dusky flying fox, the large Palau flying fox, the small Mauritian flying fox, and the Guam flying fox. Over half of the species are threatened today with extinction, and in particular in the Pacific, a number of species have died out as a result of hunting, deforestation, and predation by invasive species. Six flying fox species are believed to have gone extinct from 1864 to 2014: the Guam, large Palau, small Mauritian, dusky, large Samoan, and the small Samoan flying foxes.
Links: a. Endangered species b. Vanikoro flying fox c. Aru flying fox d. Critically endangered

Output: c

Input: Consider Input: Question: How big was the Royal Air Force the year York joined Aston Villa? Passage:York started his career with Handsworth Royal, Birchfield Rangers and the Royal Air Force, and also guested for Chelsea during World War I. In March 1915 he joined Aston Villa as an amateur, signing professional forms in August 1919. He scored one goal in 17 games in 191920, but did not feature in the 1920 FA Cup Final, which ended in a 10 victory over Huddersfield Town at Stamford Bridge. He appeared just 11 times in 192021, before going on to make 47 appearances in the 192122 campaign, as the "Villans" finished fifth in the First Division. He scored nine goals in 37 games in 192223 and five goals in 43 games in 192324. He also appeared at Wembley in the 1924 FA Cup Final, in a 20 defeat to Newcastle United. He scored seven goals in 34 matches in 192425, before hitting 20 goals in 44 appearances in 192526. He bagged 13 goals in 43 games in 192627, before being limited to just four goals in 30 appearances in 192728. He rediscovered his scoring form with 18 strikes in 48 matches in 192829, before hitting seven goals in 32 games in 192930. However he played just four times in the 193031 campaign, as Villa finished second in the league with an English record of 128 top-flight league goals scored.
Links: a. 192324 Football League b. Royal Air Force c. Huddersfield Town A.F.C. d. Royal Air Force

Output: b

Input: Consider Input: Question: What age difference was there between Anderson and his brother? Passage:Anderson was born in Edinburgh in 1832. He studied medicine at the University of Edinburgh, graduating with an MD in 1853. While at University he became interested in botany, and earned a gold medal for the best local collection of plants, and assisted in arranging the Indian herbarium. In 1854 he entered the Bengal medical service, and went to Calcutta. Subsequently he went to Delhi, where he was actively engaged during the mutiny, returning to Calcutta in 1858. His health failing, he came home, and, the steamer being detained at Aden for some days, he made an interesting collection of the plants of that region, upon which he based his 'Florula Adenensis,' published in 1860. About this time he returned to India, taking temporary charge of the Calcutta Botanic Garden during the absence of Dr Thomas Thomson, whom he afterwards succeeded as director. His brother, John Anderson was a zoologist.
Links: a. Doctor of Medicine b. Botany c. Botany d. John Anderson (zoologist)
Output: d