What factor explains the differences between boys and girls in motor performance?

What factor explains the differences between boys and girls in motor performance?
 
  a. Differences are due primarily to biological variables.
  b. Differences in boys and girls are heritable.
  c. Boys receive more encouragement and support for participating in sports.
  d. From birth, girls have less interest in sports than do boys.

Question 2

If you were to follow the advice of your authors, which of the following articles of clothing would you avoid giving to a two- or three-year-old child?
 
  a. A pair of sneakers with Velcro closures
  b. A button-down shirt
 c. A pair of shorts with a zipper
 d. A pair of sweatpants with a drawstring

Question 3

Girls tend to be well-suited to activities such as gymnastics, dancing, and balancing, due to their
 
  a. greater overall strength than boys of the same age.
  b. greater forearm strength than boys of the same age.
  c. greater limb coordination and flexibility.
  d. higher overall percentage of small tissue fat cells.