Which sentence uses a verb that agrees with its subject?

A.
A new book by J. K Rowling, the author of many fantasies, arrive in bookstores soon.

B.
The dresses on the rack in the back of the store was on sale.

C.
Their behavior during the performances was very good.

D.
The post offices in our area opens at 9 a.m.

Question

Which sentence uses a verb that agrees with its subject?	
 
 A.
A new book by J. K Rowling, the author of many fantasies, arrive in bookstores soon.
 
 B.
The dresses on the rack in the back of the store was on sale.
 
 C.
Their behavior during the performances was very good.
 
 D.
The post offices in our area opens at 9 a.m.

anonymous · Answer

For each choices, can you tell me the subject and the verb?

For example in choice A: Subject is the new book and the verb is arrive.
Do this with the other choices and we'll analyze which on is correct.