The word from the list that best fits the definition An action that rewards a particular kind of behavior is the third one: positive sanction.
Explanation:
I think that the key word to understand why positive sanction is the phrase that best fits is the word<em> reward</em>. A reward is a thing given in recognition of service, effort, achievement or any kind of behavior that is considered a good behavior. So, by knowing this, it is very easy to decide which words best fits, because a positive sanction functions as a response, as a recognition of a good behavior. It is a sanction, but is a positive one, the one given due to a good action.
In this sentence, the word rapport means connection. If you have a good connection with your audience, then they can track with you and give positive feedback
