Answer:
The correct answer will be option-D
Explanation:
Corpus callosum is a nerve tract present below the cerebral cortex found in the placental mammal only. The nerve tract is thick and wide and connects the right and light cerebral hemispheres.
The structure contains about 200 million neurons with varying degree of myelination of neurons.
The studies on corpus callosum has shown that corpus callosum is formed after 20 weeks of gestation and continuously grows after birth. The process of myelination which is the formation of myelin sheath around neurons takes place upto 8-9 years.
Thus, option-D is the correct answer.
