Definition: In this task, you're given a question, along with a context passage which has extra information available on certain terms mentioned in it, i.e., the proper nouns in the passage. Your job is to determine whether information from more than one term is needed to answer the question. Indicate your choice as `a` for Yes or `b` for No.
Input: Question: How long had the Blackwood Brothers been performing when Tony Brown traveled with them? Passage:Following stints with the Dixie Melody Boys and Trav'lers Quartets, he joined J. D. Sumner and the Stamps Quartet in 1966. In 1972, he traveled briefly with the Blackwood Brothers, thereafter joining the Oak Ridge Boys as a member of The Mighty Oaks Band. Brown also played piano for Elvis Presley. He toured with the TCB Band for much of Presley's final two years and was a part of the 1976 "Jungle Room" recording sessions at Graceland. In 1979, he joined Emmylou Harris's backing band, the Hot Band, taking over for former Presley sideman Glen D. Hardin. Brown stayed with Harris until 1981. Later, he became a session musician in Nashville and toured with acts such as Rosanne Cash.


b