Need some help please !!

Which sentence contains an adverb clause?

A.
If you visit Pennsylvania, take the self-guided, covered-bridge tour.

B.
Covered bridges remind us of days gone by.

C.
Only 1,600 covered bridges exist in the world.

D.
The Lehigh Valley, in eastern Pennsylvania, has seven covered bridges.

Respuesta :

The sentence that contains an adverb clause is A. If you visit Pennsylvania, take the self-guided, covered-bridge tour.
The other sentences are simple, which means they have only independent clauses, and no dependent ones such as an adverb clause.