Definition: 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.
Input: Question: How many hit singles did Stan Tracey have? Passage:Robert Coull Wellins was born into a showbiz family living in the Gorbals, Glasgow; he later lived in Carnwadric and attended Shawlands Academy. Wellins studied alto saxophone and harmony with his father Max, and also played piano and clarinet when young. He joined the RAF as a musician playing tenor sax. After demobilisation he played with a few Scottish bands before moving to London in the mid-1950s. He was a member of Buddy Featherstonhaugh's quintet between 1956 and 1957, together with Kenny Wheeler. Around that time Wellins also joined drummer Tony Crombie's Jazz Inc., where he first met pianist Stan Tracey, joining Tracey's quartet in the early 1960s. He also worked with Lionel Grigson in 1976. At the end of the 1970s he was a member of the Jim Richardson Quartet.
Links: a. Stan Tracey b. Lionel Grigson c. Tony Crombie d. Buddy Featherstonhaugh
Output:
a