What type of strike is designed primarily to stop a subject's forward momentum?

The correct choice focuses on the palm heel strike, which is specifically designed to counter a subject's forward momentum effectively. This striking technique utilizes the heel of the palm to deliver force against an opponent, often targeting sensitive areas such as the face or upper body. By directing the strike in a way that disrupts the opponent's balance and movement, it serves to halt their forward motion, preventing them from progressing towards the individual delivering the strike.

In contrast, other options do not align with the primary purpose of stopping forward momentum. For instance, a palm foot strike typically involves using the palm as a method to strike or push without the same focus on stopping an advance. A mandible runner, on the other hand, does not refer to a recognized striking method and is likely a term intended to confuse or mislead. Therefore, the palm heel strike is the most suitable answer for the specific intent of halting a subject's forward progress effectively.