The sentence that contains an action verb is, 'Some Romans thought very highly of their emperor.'
Answer: Option A
Step-by-step explanation:
An action Verb is a verb which is used to express the ‘actions’ of a subject. Now this action can either be physical one or mental one explaining us what the subject is doing.
In the sentence, Some Romans thought very highly of their emperor’ we can say that the action Verb is ‘thought.’ Thought expresses Romans act of mental thinking.
If we take a look at other options mentioned, we can notice that they’ve used words such as ‘grew unhappy’, ‘were happy’, ‘became angry’ these words expresses the emotions and not actions. Thus, Option 3 contains an action verb which is ‘thought.’