Question

a source that has credibility is
○ reliable.
○ questionable.
○ popular.
○ old.

Explanation:

To determine the answer, we analyze the meaning of "credibility". A credible source is one that can be trusted or relied upon. "Reliable" means able to be trusted or depended on, which matches the concept of credibility. "Questionable" implies doubt, "popular" refers to being well - liked, and "old" refers to age, none of which relate to credibility.

Answer:

A. reliable.