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: How many years did Nick Van Exel play for the Nuggets? Passage:The 1998–99 NBA season was the Nuggets' 23rd season in the National Basketball Association, and 32nd season as a franchise. During the offseason, the Nuggets acquired Nick Van Exel from the Los Angeles Lakers, and second-year guard Chauncey Billups from the Toronto Raptors. Despite the return of Antonio McDyess, who was re-signed by the team after one season with the Phoenix Suns, the Nuggets continued to struggle under new head coach Mike D'Antoni losing eight of their first nine games. Top draft pick Raef LaFrentz out of Kansas was out for the remainder of the season with a knee injury after playing just twelve games. The Nuggets finished the lockout shortened season sixth in the Midwest Division with a 14–36 record. This was also their final season playing at McNichols Sports Arena. Following the season, second-year forward Danny Fortson and Eric Williams were both traded to the Boston Celtics, and D'Antoni was fired as coach.
 Links: a. Nick Van Exel b. Raef LaFrentz c. 1997–98 Los Angeles Lakers season d. Antonio McDyess
Example Output: a

Example Input: Question: Who did the 197th fight against in the Battle for Caen? Passage:After spending many years training in the United Kingdom the 197th Brigade, together with the rest of the 59th Division, landed in France on 29 June 1944, D-Day + 23. The division, under command of XII Corps, became part of the British Second Army, which was engaged in the Battle for Caen. With the arrival of the 59th Division General Bernard Montgomery, commanding the Anglo-Canadian 21st Army Group, decided to renew the offensive to capture the city of Caen, which was originally a D-Day objective for the British 3rd Infantry Division which ultimately failed, due mainly to heavier resistance than expected. Operation Charnwood. The brigade's first action was Operation Charnwood with 2/6th South Staffords (of 177th Brigade), along with C Company of the 7th Battalion, Royal Northumberland Fusiliers (the divisional MG Battalion), together with numerous units of the Royal Artillery under command (and 510 Field Company, RE), and supported by the Churchill tanks of the 1st East Riding Yeomanry (of 27th Armoured Brigade). The brigade suffered comparatively light casualties in Charnwood. The 197th Brigade later fought in the Second Battle of the Odon, and the Battle of the Falaise Gap.
 Links: a. Battle for Caen b. Bernard Montgomery c. General (United Kingdom) d. 21st Army Group
Example Output: a

Example Input: Question: How many years did the person who possibly encouraged Eumenes to revolt reign? Passage:Although nominally under Seleucid control, Pergamon under Philetaerus enjoyed considerable autonomy. However, upon his succession, Eumenes, perhaps with the encouragement of Ptolemy II, who was at war with the Seleucids, revolted, defeating the Seleucid king Antiochus I near the Lydian capital of Sardis in 261 BC. He was thus able to free Pergamon, and greatly increase the territories under his control. In his new possessions, he established garrison posts in the north at the foot of Mount Ida called Philetaireia after his adoptive father, and in the east, northeast of Thyatira near the sources of the river Lycus, called Attaleia after his grandfather, and he extended his control south of the river Caïcus to the Gulf of Cyme as well. Demonstrating his independence, he began to strike coins with the portrait of Philetaerus, while his predecessor had still depicted Seleucus I Nicator.
 Links: a. Ptolemy II Philadelphus b. Seleucid Empire c. Bakırçay d. Seleucus I Nicator
Example Output:
a