In this task, you're given a question, along with a context passage. The passage will not have a direct answer to the question, but can include some information and a clue for the answer. Assuming you can only obtain information about one entity in the passage, your job is to determine whether information from the passage can be used to answer the question. Indicate your choice as 'a' for Yes or 'b' for No.

Ex Input:
Question: How long had Jeffrey Ullman been teaching at Stanford the year Mairson got his B.A.? Passage:Mairson received a B.A. in Mathematics from Yale University in 1978 and a Ph.D. in Computer Science from Stanford University in 1984 under the supervision of Jeffrey Ullman. His Ph.D. thesis, The Program Complexity of Searching a Table, won the Machtey Award at the 1983 IEEE Symposium on Foundations of Computer Science (FOCS). Mairson was a Postdoctoral researcher at INRIA Rocqencourt from 1984 to 1985, at Stanford University in 1985, and at the University of Oxford in 1986. He held a Visiting Professor position from 1999 to 2001 at Boston University. From 2005 to 2007, Mairson has served as the Chair of the Faculty Senate at Brandeis. He is currently an Associate Editor of the journal Logical Methods in Computer Science and Information and Computation, and sits on the editorial board of Higher-Order and Symbolic Computation.

Ex Output:
b

Ex Input:
Question: Which Super Kings player who were ahead of Badree in team depth is the oldest? Passage:Badree first played for an overseas Twenty20 franchise in January 2013, when he played for the Khulna Royal Bengals in the 2013 Bangladesh Premier League (BPL) season. Later in the year, he signed with the Rajasthan Royals for the 2013 Indian Premier League (IPL), although he played only a single game (against the Delhi Daredevils). In the 2014 IPL auction, Badree was bought by the Chennai Super Kings for US$50,000. He went on to play four matches for the team during the 2014 season, but took only two wickets, with Ravichandran Ashwin and Ravi Jadeja being the preferred spin options. Later in 2014, Badree signed with the Brisbane Heat for the 201415 Big Bash League season in Australia. He was unable to play any matches due to a shoulder injury, but re-signed for the 201516 season. He struggled for form early in the season, going wicketless in his first three games, but eventually bounced back to finish as his team's leading wicket-taker, with nine wickets from eight matches. This included 5/22 in the final game of the season, against the Melbourne Stars.

Ex Output:
b

Ex Input:
Question: Who succeeded Khalid's son as ruler of the family's stronghold? Passage:Khalid was a member of the Shayban tribe, dominant in the region of Diyar Bakr in the northern Jazira, and third son of Yazid ibn Mazyad al-Shaybani, who served twice as Arab governor (ostikan) of Arminiya (a large province encompassing the whole of Transcaucasia). Khalid served in the same office no less than four times: in 813/814, 828832, briefly in 841 and again under Caliph al-Wathiq (r. 842845). In his first tenure, he showed himself conciliatory towards the native Christian population and the nakharar princes, but his second tenure was marked by the brutal suppression of several revolts by local Arab magnates, as well as the harsh treatment of the Christian population. As a result, when his re-appointment to the office was announced in 841, a rebellion broke out, forcing the Abbasid government to recall him immediately. Nevertheless, al-Wathiq assigned Arminiya to Khalid. The latter arrived in the province at the head of an army, and crushed any opposition. He died soon after at Dvin, where he was buried. He was succeeded by his son, Muhammad. His younger son Haytham ibn Khalid ruled in the family's stronghold of Shirvan, and was the first to claim the title of Shirvanshah.

Ex Output:
b