(d) All of the above
The brain is responsible for thinking, regulating the heartbeat as well as balancing the body. It consists of different parts like the Cerebrum, Cerebellum, the Medulla Oblongata which control and coordinate different functions in the body. For instance, the brain stem which includes midbrain, medulla oblongata, and the pons controls breathing, heartbeat, sneezing, eye blinking, and swallowing. Body temperature and hunger are also controlled by parts of the brain stem.