A Study That Followed Children Who Attended the Perry Preschool

A study that followed children who attended the Perry Preschool Program in Ypsilanti, Michigan, for more than 35 years found that in comparison with same-age children who did not attend the program, the children who did attend had:

A) higher achievement scores at the ages of 9 and 14.
B) higher achievement scores at the age of 9, but not at the age of 14.
C) higher achievement scores at the age of 14, but not at the age of 9.
D) similar achievement scores to those in the control group at ages 9 and 14.