Answer : a. as long as you're going to the store
The adverb clause of the statement, "As long as you're going to the store, would you buy some bananas?" is the clause "as long as you're going to the store". An adverb clause must be made up of a subject and a verb and must also contains a subordinate conjunction that makes the clause unable to express a complete thought and of course the clause must be able to answer the wh's questions why, when, where and how.
