Identify the following clause: when she paints the room, it will look much better in here.
a. adjective clause
b. adverb clause
c. independent clause

B. Adverb clause

Example:
This year's fireworks show must have been expensive, which is an annual holiday tradition.

This phrase could have been
This year's fireworks show, which is an annual holiday tradition, must have been expensive.

A clause is segment in a sentence that can stand on its own since it has its own subject and predicate.
Adjective clause is one type of clause that describes a noun or pronoun in the sentence
Another is, adverb clause.