When Morrison Et Al

Multiple Choice

When Morrison et al., compared the cognitive performance of children who had just made the age cutoff for entering first grade with children who had just missed the cutoff and spent the year in kindergarten, they found

A) no difference in cognitive skills for these two groups.
B) higher performance on language, but not math, for the first-grade group.
C) higher performance on math, but not language, for the first-grade group.
D) higher performance in both math and language for the first-grade group.