With minor variations, the average age of menarche in most developed countries is ____
a. 9 to 10 years c. 12 to 13 years
b. 10 to 11 years d. 13 to 14 years
C
Psychology
a. 9 to 10 years c. 12 to 13 years
b. 10 to 11 years d. 13 to 14 years
C