What Is the Difference Between Sex and Gender

What is the difference between sex and gender?

A) Sex refers to sexual orientation, and gender refers to physical or physiological differences between males and females.
B) Sex is the extent to which one identifies as being either masculine or feminine, gender is biological characterization of anatomy.
C) Sex refers to who a person is sexually attracted to, and gender refers to whom a person chooses to partner with.
D) Sex refers to physical or physiological differences between males and females, while gender is the extent to which one identifies as being either masculine or feminine.