Answer: B) Steven was worried about his driving test.
Explanation: a word used to describe an action, state, or occurrence, and forming the main part of the predicate of a sentence. An action verb explains what the subject of the sentence is doing or has done (it can be a physical or a mental action). From the given options, the sentence that contains a mental action verb, is the corresponding to option B: Steven was worried about his driving test, because "was worried" is an action happening in Steven's mind.