Malcolm Had Been a Professional Hockey Player with a Great

Malcolm had been a professional hockey player with a great sense of his position in space. Even after retiring from professional hockey Malcom continued to play in seniors' hockey leagues. During one of those seniors games, John (a player on the opposite team) knocked Malcolm to the ice and Malcolm hit his head hard enough to acquire brain damage. After the accident, John developed an enormous amount of guilt, which prompted him to enrol in Introduction to Psychology to learn more about brain function and neuroscience.
-Ever since the accident Malcolm can no longer concentrate and his smoking habit has increased.This is could be because the nicotine in the cigarettes is an agonist for_____ and causes _____.

A) acetylcholine; PSPs
B) acetylcholine ;IPSPs
C) serotonin; PSPs
D) serotonin; IPSPs