You Recently Read a Study in Which the Researchers Concluded

You recently read a study in which the researchers concluded that after age 60, women's IQs drop dramatically.This conclusion was based upon comparisons of women born between 1910-1930 and women born between 1960- 1980.Based upon this information, the comment you would most likely make is

A) this is not a valid result because men were not included in the study.
B) longitudinal research doesn't work well when looking at IQ over time.
C) cohort effects likely account for the observed differences.
D) whoever conducted this study is negatively biased against older women.