Malcolm is driving to work on the interstate when a truck cuts in front of him. Malcolm slams on the brakes and avoids an accident. His heart is racing and he feels relief and anger simultaneously. In this instance, Malcolm's stress reaction is

His pounding heart

Explanation:

Stress reaction may be described as a sensation which resonates in a individual whenever there is a an attack or a sudden threatening scenario. When such scenario occurs, the person will try as much as possible to prevent getting harmed or sustaining injuries. The sensation which the person could be termed as a reaction which the person feels maybe referred to as the stress reaction. In Malcolm's case, His pounding heart which resulted from the threatening scene of a possible accident is his stress reaction.

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