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.

[EX Q]: Question: How many years did the owner of the private observatory live? Passage:It would seem that Gill's interests lay elsewhere since after a few years he sold the business, and then spent time equipping Lord Lindsay's private observatory at Dun Echt, Aberdeenshire. In 1874, Gill joined the expedition to Mauritius to observe the transit of Venus. Three years later he went to Ascension Island to observe a near approach of Mars and to calculate its distance. While carrying out these laborious calculations, he was notified of his appointment to the Cape Observatory, which, over the following 27 years he was to refurbish completely, turning it into a first-rate institution. Gill was a meticulous observer and had a flair for getting the best out of his instruments. His solar parallax observations with a heliometer and his calculations of distances to the nearer stars, are testimony to his outstanding work. He recruited Robert Innes to the Cape Observatory.
 Links: a. South African Astronomical Observatory b. Aberdeenshire (historic) c. James Lindsay, 26th Earl of Crawford d. South African Astronomical Observatory
[EX A]: c

[EX Q]: Question: In what year did Ivan write Smrt Smail-age Čengića? Passage:Travelogue writer, brother of more noted Ivan, the writer of the well-known epic Smrt Smail-age Čengića. He attended a German school in his native town, where he was trained to become a blacksmith. Often he indulged into travels (Montenegro, Serbia), and exceptionally in a few occasions to Bosnia. In 1841 he was back to Novi, practicing his craft and agriculture, but also engaging in literature and cultural issues in general. In 1847 he ended up in Vienna, in 1848 again in Bosnia (in Sarajevo, at the court of Fazli-paša Šerifija). At the end of 1848, in a letter addressed to his brothers he says: "I don't know when I shall return home, for I have been, I'm afraid, created for this country. Turks are very fond of me for my prudence, they say, and rayah grows ever more trust in me, and therefrom there is no other outcome but mitre on the head or a stake in the arse". After Sarajevo, Matija went to Istanbul (though the exact dates cannot be ascertained), and according to some legends even further, to Suez and the Egypt. In 1852 Matija was back to Novi, where he settled until growing ill in 1879. He lived a secluded life until the symptoms of mind degeneration have started to show, finally dying in the sanatorium of a well-known psychiatrist Richard von Krafft-Ebing, near Graz, on April 17, 1881.
 Links: a. Rayah b. Blacksmith c. Ivan Mažuranić d. Rayah
[EX A]: c

[EX Q]: Question: How many plans are currently being held at RAF Mildenhall? Passage:The Strategic Air Command (SAC) initially operated DC-130s assigned to its 100th Strategic Reconnaissance Wing (100 SRW) at Davis–Monthan AFB, Arizona from 1966 through 1976. In 1976, the 100th's DC-130s and drone assets were transferred to the 432nd Tactical Drone Group of Tactical Air Command (TAC) at Davis–Monthan AFB. Concurrent with this action, the 100 SRW's U-2 aircraft assets were transferred to the 9th Strategic Reconnaissance Wing (9 SRW) and merged with the latter's SR-71 aircraft assets at Beale AFB, California. The 100 SRW was then re-designated as the 100th Air Refueling Wing (100 ARW) and relocated to Beale AFB, operating KC-135 Stratotanker aircraft, until its later reassignment to its current home of RAF Mildenhall, United Kingdom.
 Links: a. 100th Air Refueling Wing b. Lockheed U-2 c. Beale Air Force Base d. RAF Mildenhall
[EX A]:
d