The correct option is A Cerebellum
Cerebellum is one of the parts of the hind brain that controls the rapid muscular activities, such as running, talking. The other two parts of he hindbrain are pons varolii and medulla oblongata.
Hypothalamus is part of diencephalon of the forebrain and it controls body temperature, growth and sexual behaviour. It is an important link between neural and endocrine system.
The spinal cord is a long, thin, tubular bundle of nervous tissue and support cells that extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column.
Corpus callosum is a tract of nerve fibres that connects the left and right hemispheres of the brain.