Freezing-up or being unable to move or respond physically during a traumatic event is an example of

shock

Explanation:

Freezing up during a traumatic event is an example of freeze behavior or freeze response.

Explanation:

The freezing response is our body’s natural physical response triggered when we are encountered with extreme trauma or threat that makes us immobilized and paralyzed.

This happens when we are facing a situation wherein we choose to neither fight or flee from that traumatic situation. In other words, it is one of the ways of the defense mechanism of our body to makes us feel less sensitive to the danger, pain or injury that we are facing.