Explanation
The correct answer to the analogy "PLAY is to ACTOR as CONCERT is to _____?" is B: Musician.
In this analogy, the relationship between "play" and "actor" is that an actor performs in a play. Similarly, the relationship between "concert" and the answer choice must be that a musician performs in a concert.
Option A, Symphony, is not a suitable answer because a symphony is a type of musical composition, not a person who performs in a concert. Option C, Piano, and Option D, Percussion, are also not suitable answers because they are specific musical instruments, not performers.
Therefore, the best answer choice is B: Musician, which refers to a person who performs music and could be part of a concert performance.
Hence, the correct answer is B: Musician.
