Compared to a comparison group of children with low SES who did not attend Head Start, those children who did  a. were less likely to be placed in special education classes.  b. improved their...

Compared to a comparison group of children with low SES who did not attend Head Start, those children who did

 a. were less likely to be placed in special education classes.

 b. improved their academic performance, but were still more likely to repeat at least two grades.

 c. showed a boost in IQ and achievement that lasted throughout their school years.

 d. showed no differences in academic performance and success.