What Evidence Did Money and Ehrhardt Use as the Basis

What evidence did Money and Ehrhardt use as the basis for concluding that there is a critical period for the establishment of gender identity?

A) Hormones must be released prenatally to have any impact on behavior.
B) Sex reassignment can be successfully done when a child has achieved gender identity,but not once a child has achieved gender stability.
C) Sex reassignment before 18 months of age causes few adjustment problems,while reassignment after 3 years of age is very difficult.
D) Sex reassignment while still in the preoperational stage of development causes few adjustment problems,while reassignment once concrete operational thought has begun is very difficult.