What is the difference between "sex" and "gender," if any?

a. Sex and gender are interchangeable terms, both meaning the cultural categories of "male" and "female."
b. Sex and gender are interchangeable terms, both meaning the biological status of being male or female.
c. Gender refers to the biological status of being male or female. Sex refers to the cultural categories of "male" and "female."
d. Sex refers to the biological status of being male or female. Gender refers to the cultural categories of "male" and "female."

Sex refers to the biological status of being male or female. Gender refers to the cultural categories of "male" and "female."