A Young Woman Who Formerly Had a Fairly High Sex

A young woman who formerly had a fairly high sex drive, and who reports no new medical problems, nonetheless experiences an unexpected drop in sex drive. What would be an important question to ask her, before recommending some sort of psychotherapy?

A) "Have you been exposed to high levels of testosterone lately?"
B) "Have you recently started taking birth control pills?"
C) "Have you recently stopped using marijuana?"
D) "Have you experienced lower levels of prolactin lately?"