What Is One Significant Reason for the Advances in Fine

What is one significant reason for the advances in fine motor skills shown by children 6 to 8 years old?

A) Children have lived long enough to acquire practice with fine motor skills.
B) Children's cognitive development is increasing.
C) Children have greater opportunities to model fine motor skill behaviors from others.
D) The amount of myelin in the brain increases to protect,insulate,and surround neurons.