What Happens to the Number of Neurons in a Monkey's

What happens to the number of neurons in a monkey's brain over the course of development?

A) Monkeys acquire 35% of their adult neurons after birth.
B) Monkeys lose 35% of their visual cortex neurons between birth and adulthood.
C) Monkeys lose 5% of their neurons after birth.
D) The number of neurons in a monkey's brain remains relatively constant after birth.