Which of the following terms refers to the biologically influenced characteristics by which people define male and female?

A) gender
B) transgender
C) sex
D) androgyny

Sex refers to the biological differences between males and females, including reproductive organs, chromosomes, and hormones. This is in contrast to gender, which refers to the socially constructed roles, behaviors, and expectations associated with being male or female, and can vary across different cultures and societies. Transgender refers to individuals whose gender identity does not align with the sex they were assigned at birth, while androgyny refers to a combination of masculine and feminine characteristics in a person's appearance or behavior.