According to a Study of More Than 10,000 American Adolescents

According to a study of more than 10,000 American adolescents, approximately ________ of teenagers report having an anxiety disorder by age 18 and ________ of these individuals had already developed an anxiety disorder before turning 12.

A) two-thirds; almost none
B) one-third; almost all
C) 50%; over 90%
D) 15%; just over half