Question

Which sentence uses periods correctly?

A.
The US flag flew in front of the building on E. Main St. in the town square.

B.
The U.S. flag flew in front of the building on E Main St in the town square.

C.
The US flag flew in front of the building on E. Main St in the town square.

D.
The U.S. flag flew in front of the building on E. Main St. in the town square.