decided is the action verb because the subject, I is doing the action of deciding.
Answer:
The action verb in I decided that even a hot day in Arizona feels comfortable because of the low humidity is decided.
Explanation:
An action verb are verbs that describe what the subject is doing by expressing an action -mental or physical. In this case, the subject is I and the action verb is decided, because is the verb that describes what the subject did by defining the mental action.
