(B) is the right answer.
The dorsal portion of the midbrain consists mainly of four round swellings (lobes) called corpora quadrigemina. Pons consists of fibre tracts that interconnect different regions of the brain. Cerebellum has very convoluted surface in order to provide the additional space for many more neurons. The medulla of the brain is connected to the spinal cord. The medulla contains centres which control respiration, cardiovascular reflexes and gastric secretions.