Answer:
tapping on the podium with the fist
Explanation:
Body gestures such as "tapping on the podium with the fist" are often used by good speakers to help make their points and to keep the audience engaged.
This is because "tapping on the podium with the fist" gives a sound like exclamation that drives home a point that tends to show the power and confidence on the part of the speaker.
Option B: rapidly tapping one foot on the floor: shows impatience or releasing of tension. Hence, this is not correct.
Option C. making a hand movement for the listener to come towards the speaker: is a means of asking someone to come forward only, not necessarily to express or give credence to a point. Hence, this is not correct as well.