What Is a Common Criticism of Many of the Studies

What is a common criticism of many of the studies related to childhood sexuality (e.g., information from Kinsey's data of 1948 and 1953) ?

A) Most are completed using participants who have experienced childhood sexual abuse.
B) Most do not ask children questions directly but rely on parents to judge their children's sexuality development.
C) Most are retrospective in nature and rely on older adults to remember what they did when they were young.
D) More studies have relied on information from girls because they are more likely to be open about their early childhood experiences.