The cerebellum is responsible for receiving the sensory information from various brain parts, spinal cord and sensory system and control the motor movement of the body. So the cerebellum is responsible for controlling the voluntary movement of the body like posture, balance, coordination, etc.
Therefore when anyone drinks a large amount of alcohol he loses control of his voluntary movement due to the dysfunction of the cerebellum, as a result, cannot coordinate their movements or walk a straight line. Therefore the correct answer is the cerebellum.
