The Speech Given by Former Harvard University President Lawrence Summers

The speech given by former Harvard University president Lawrence Summers speculated that

A) the low numbers of women found in engineering and physics might be due in part to innate differences between men and women.
B) intrinsic differences between men and women might be due in part to socialization factors.
C) intrinsic differences between men and women might be due to discrimination.
D) there exist no differences between men and women that cannot be explained by cognitive theory.
E) there exist no differences between men and women that cannot be explained by biological mechanisms.