Which blood vessels play a key role in regulating blood distribution and pressure because their diameters may be easily and rapidly adjusted?

i think c is correct.

the answer is: give 30 chest compression

when we choke on foods, the pathway that we use to breath is blocked and prevented air from coming into our body. this could resulted in death within minutes after occurrence. because of this, after witnessing such choking accidents, we need to call 911 and immediately give the chest compression in order to open up a pathway for air to come in.