Question

Which sentence contains a verb in passive voice?

A.
A suspicious man was seen lurking around the complex by several neighbors.

B.
Their cat must eat at least five times a day.

C.
Is that my tennis racket?

D.
These old books might be quite valuable.

I think it's either A. A suspicious man was seen lurking around the complex by several neighbors or B. Their cat must eat at least five times a day. Which one? Will give medal and become fan of anyone who even tries!