The option that is not an Action Verb is; D: Happy
<h3>What is an action verb?</h3>
An action verb is simply defined as a verb that describes different actions such as run, jump, kick, eat, break, cry, smile e.t.c.
Now, in the question, trained, tested and designed are action verbs because they describe actions that are performed by people whereas being happy is not an action but a feeling.
Read more about Action verb at; brainly.com/question/678435
