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.

Example Input: Question: Which ship had been in service longer at the time when he was on them, the one where he still held sub-lieutenant rank or the one where David had been promoted to full lieutenant? Passage:He was assigned as a midshipman on 1 May 1929 after finishing top of his class in five subjects. In 1930 he was assigned to the battleship Marlborough, part of the Third Battle Squadron; and the following year to the battlecruiser in September 1931 on which he served with fellow midshipman, and future vice admiral, Peter Gretton. While serving on the ship, Wanklyn was promoted to acting sub-lieutenant (the equivalent of an army second lieutenant) on 1 January 1932. Soon afterwards he moved to the naval gunnery school - HMS Excellent - at Whale Island, Portsmouth to learn more about naval navigation to qualify for his second ring at the rank of lieutenant. In February 1933 he moved to HMS Dolphin and was promoted to lieutenant on 1 February 1933.

Example Output: b

Example Input: Question: What is the maximum length of the species that is known to prey on the crossback stingaree? Passage:The broadnose sevengill shark (Notorynchus cepedianus) is known to prey on the crossback stingaree. When threatened, this ray raises its tail warningly above its body in a scorpion-like fashion. Parasites documented from this species include a tapeworm in the genus Acanthobothrium, and the monogenean Calicotyle urolophi. Like other stingrays, the crossback stingaree is aplacental viviparous: when the developing embryos exhaust their supply of yolk, their mother provisions them with nutrient-rich histotroph ("uterine milk") through specialized extensions of the uterine epithelium called "trophonemata". Females produce litters of 1–4 pups every other year. Embryonic development proceeds rapidly over a six-month period, though the total gestation period may be much longer if there is a period of dormancy for the eggs after fertilization, as has been reported in other stingarees. Off Tasmania, large estuaries such as at the mouth of the River Derwent serve as nursery areas.

Example Output: b

Example Input: Question: When did the conductor at Midori's concert debut begin conducting the New York Philharmonic? Passage:Midori gave her first public performance at the age of six, playing one of the 24 Caprices of Paganini in her native Osaka. In 1982 she and her mother moved to New York City, where Midori started violin studies with Dorothy DeLay at Pre-College Division of Juilliard School and the Aspen Music Festival and School. As her audition piece, Midori performed Bach's thirteen-minute-long Chaconne, generally considered one of the most difficult solo violin pieces. In the same year, she made her concert debut with the New York Philharmonic under Zubin Mehta, a conductor with whom she would later record on the Sony Classical label. In 1986 came her legendary performance of Leonard Bernstein's Serenade at Tanglewood, conducted by Bernstein. During the performance, she broke the E string on her violin, then again on the concertmaster's Stradivarius after she borrowed it. She finished the performance with the associate concertmaster's Guadagnini and received a standing ovation. The next day The New York Times front page carried the headline, "Girl, 14, Conquers Tanglewood with 3 Violins".

Example Output:
b