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 are earthwork mounds made of? Passage:Indigenous peoples inhabited Missouri for thousands of years before European exploration and settlement. Archaeological excavations along the rivers have shown continuous habitation for more than 7,000 years. Beginning before 1000 CE, there arose the complex Mississippian culture, whose people created regional political centers at present-day St. Louis and across the Mississippi River at Cahokia, near present-day Collinsville, Illinois. Their large cities included thousands of individual residences, but they are known for their surviving massive earthwork mounds, built for religious, political and social reasons, in platform, ridgetop and conical shapes. Cahokia was the center of a regional trading network that reached from the Great Lakes to the Gulf of Mexico. The civilization declined by 1400 CE, and most descendants left the area long before the arrival of Europeans. St. Louis was at one time known as Mound City by the European Americans, because of the numerous surviving prehistoric mounds, since lost to urban development. The Mississippian culture left mounds throughout the middle Mississippi and Ohio river valleys, extending into the southeast as well as the upper river.
 Links: a. Archaeology b. Collinsville, Illinois c. Earthworks (archaeology) d. Collinsville, Illinois
Example Output: c

Example Input: Question: During which centuries were the Kyoto Imperial Palace and the Sento Imperial Palace home to the Emperors of Japan? Passage:With its 2,000 religious places – 1,600 Buddhist temples and 400 Shinto shrines, as well as palaces, gardens and architecture intact – it is one of the best preserved cities in Japan. Among the most famous temples in Japan are Kiyomizu-dera, a magnificent wooden temple supported by pillars off the slope of a mountain; Kinkaku-ji, the Temple of the Golden Pavilion; Ginkaku-ji, the Temple of the Silver Pavilion; and Ryōan-ji, famous for its rock garden. The Heian Jingū is a Shinto shrine, built in 1895, celebrating the Imperial family and commemorating the first and last emperors to reside in Kyoto. Three special sites have connections to the imperial family: the Kyoto Gyoen area including the Kyoto Imperial Palace and Sentō Imperial Palace, homes of the Emperors of Japan for many centuries; Katsura Imperial Villa, one of the nation's finest architectural treasures; and Shugaku-in Imperial Villa, one of its best Japanese gardens. In addition, the temple of Sennyu-ji houses the tombs of the emperors from Shijō to Kōmei.
 Links: a. List of emperors of Japan b. List of emperors of Japan c. Kyoto Imperial Palace d. Kinkaku-ji
Example Output: c

Example Input: Question: What is the capital of Punjab province? Passage:Hailing from the business-industrialist family from the Punjab Province of Pakistan, Hussain graduated from the FC College University and the Punjab University. After his graduation, Hussain subsequently joined the family business comprising large numbers of industries, textiles, agricultural farms, sugar and flour mills. He successfully contested in the non-partisan 1985 elections and was appointed as minister of industry in the government of Prime minister Muhammad Junejo, lasting until 1988. Hussain became a leader and influential conservative figure in the Islamic Democratic Alliance (IDA) between 1988 and 1990 and joined the Pakistan Muslim League (PML) under Nawaz Sharif in 1993. Hussain served as the 26th Interior minister in the government of Prime minister Nawaz Sharif in two non-consecutive terms from 1990 to 1993 and 1997 to 1999.
 Links: a. Muhammad Khan Junejo b. Punjab, Pakistan c. Nawaz Sharif d. Ministry of Industries and Production (Pakistan)
Example Output:
b