Answer: Pause
Explanation:
Gist s simply means when there's a break or a pause in a certain activity. For example, in the question given "Halftime is a hiatus in the action of a football game", it simply means that during halftime, there's a pause or a break as each team goes to the dressing room and rest for few minutes before coming back to the field for the second half.
Therefore, the correct option is D.