One of the Main Arguments Surrounding the Inclusion of Gender

One of the main arguments surrounding the inclusion of gender identity disorder in the DSM-IV-TR is

A) that its inclusion pathologizes a natural phenomenon which is often found in the animal kingdom.
B) that GID is more of a medical disorder than a psychological disorder.
C) that due to its rarity,GID should be re-labeled as a sexual disorder NOS.
D) that its inclusion encourages people to adopt behaviors of the opposite sex.