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 Input: Question: What is Lorraine Copeland's field of study? Passage:It was first studied by Lorraine Copeland and Peter Wescombe in 1965–1966. A wide variety of materials were recovered from the site and its immediate area that are now held in the Saint Joseph University in Beirut. Stone tools from the surface included numerous short, wide, sickle blades with fine denticulation or nibbling along with tanged arrowheads, scrapers, chisels, axes, burins, obsidian and a small green stone axe. Pottery resembled middle periods at Byblos and coloured similar to at Ard Tlaili with red or black washes. Both fine and coarse shards were found of jars with a variety of collared and flared necks and flat bases along with bow rims such as those found at Jericho. Vessels were decorated with stabbed and incised designs, finger pressed around the rim and smoothed by hand or with straw. A painted lattice pattern was detected on at least one piece. Comparisons were made with middle and late Neolithic periods at Byblos showing inhabitation from several phases. The site was also used in Bronze Age and Classical times and material from these phases has been found over a wide area around the site.
 Links: a. Beirut b. Lorraine Copeland c. Axe d. Arrowhead
Example Output: b

Example Input: Question: During what years was the Early Bronze Age? Passage:Iran is home to one of the world's oldest continuous major civilizations, with historical and urban settlements dating back to 7000 BC. The south-western and western part of the Iranian Plateau participated in the traditional Ancient Near East with Elam, from the Early Bronze Age, and later with various other peoples, such as the Kassites, Mannaeans, and Gutians. Georg Wilhelm Friedrich Hegel calls the Persians the "first Historical People". The Medes unified Iran as a nation and empire in 625 BC. The Achaemenid Empire (550–330 BC), founded by Cyrus the Great, was the first true global superpower state and it ruled from the Balkans to North Africa and also Central Asia, spanning three continents, from their seat of power in Persis (Persepolis). It was the largest empire yet seen and the first world empire. The Achaemenid Empire was the only civilization in all of history to connect over 40% of the global population, accounting for approximately 49.4 million of the world's 112.4 million people in around 480 BC. They were succeeded by the Seleucid, Parthian, and Sasanian Empires, who successively governed Iran for almost 1,000 years and made Iran once again as a leading power in the world. Persia's arch-rival was the Roman Empire and its successor, the Byzantine Empire.
 Links: a. Bronze Age b. Cyrus the Great c. Persepolis d. Central Asia
Example Output: a

Example Input: Question: Which of the tournaments that Serena Williams' played in 1997 in the qualifying round is the oldest? Passage:Williams played the qualifying rounds of her first three tournaments of 1997, in the first round of State Farm Evert Cup, third round of Acura Classic and second round of European Indoor Championships, to Alexia Dechaume-Balleret, Magui Serna and Dominique Monami respectively. She then qualified for her first tour main draw when she defeated Magui Serna in the final round of qualifying at the Kremlin Cup, but lost in the first round of the main draw to compatriot Kimberly Po. She then entered the Ameritech Cup as a wild card and ranked no. 304. She earned her first main draw win against then world no. 27 Elena Likhovtseva in straight sets. In the next round, she upset world no. 7 Mary Pierce in two tight sets, with Williams failing to serve it out in the twelfth game of the second set but eventually won in a tie-break. In the quarterfinal she upset world no. 4 Monica Seles easing through the second and third sets, recording her first career wins over top 10 players and becoming the lowest-ranked player in the open era to defeat two top 10 opponents in one tournament. She ultimately lost in the semifinals to world no. 5 Lindsay Davenport 4-6 in both sets.
 Links: a. Monica Seles b. Ameritech Cup c. Indian Wells Masters d. Zurich Open
Example Output:
c