Aslap on the back is more painful than a pat on the back because a slap triggers:
a. the release of endorphins.
b. more intense neural impulses.
c. the release of serotonin.
d. more neurons to fire, and to fire more often.

option B

Explanation:

slap on the back is considered to be a strong enough stimulus to generate a nerve impulse which causes more pain because of sudden rush of neuronal impulse.

Any slap can give you a physical injury unintentionally. and slap on back ban results in back pain and in some cases leads to some serious condition so its better to avoid this.

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answer; i believe the correct answer is norming;