The correct answer is GABA.
GABA is a neurotransmitter, which functions by shielding certain impulses fired between nerve cells in the brain. Low level of GABA result in chronic pain, anxiety, epilepsy, sleep disorder, etc. Alcohol and GABA have similar effects on the brain, because alcohol is an agonist of GABA receptors, that is, alcohol has the capacity to bind to some brain GABA receptors and produce the same effects as that of GABA. This action increases the amount of dopamine and serotonin that is released into the brain leading to production of pleasurable feelings and emotions. Continuous exposure of GABA receptors to alcohol over a long period of time will lead to insensitivity of the GABA receptors and ultimately to alcohol addiction.
