Question

A piano goes in the _____________.

A. Brass section
B. Piano section
C. Strings section
D. Percussion section

Answer 1

Percussion section would be your answer. 

Answer 2

Violin goes in the strings section.
Drum goes in the percussion section.
Trombone goes in the brass section.
And...
piano goes in the percussion section.
Wait... whaa?

That's because a piano section doesn't exist!