Answer:
a. plays a role in analgesia and the rewarding effects of morphine.
Step-by-step explanation:
Mu receptors are receptors that have a strong analgesic action. These receptors are opioid receptors, which are cellular receptors for neurotransmitters present in the human nervous system, to which opioids attach. As already mentioned, the mu receptor has a strong analgesic action and plays a role in analgesia and the gratifying effects of morphine.