Which of the following is an example of a high order explosion characteristic?

A high order explosion is characterized by a rapid and violent release of energy, resulting in an instantaneous and significant increase in pressure. The key characteristic of such explosions is the rapid pressure rise that occurs within a very short period. This rapid increase in pressure can lead to destructive effects, including shock waves and extensive damage to surrounding structures.

In contrast, other characteristics mentioned, such as slow pressure rise or events that occur at subsonic speeds, are indicative of lower order explosions or non-explosive events. These do not correlate with the quick and high-energy release typical of high order explosions. Therefore, the rapid pressure rise is a clear indication of a high order explosion, confirming its status as a key distinguishing feature.