The "One-Sex Model" Refers To

The "One-Sex Model" refers to:

A) Modern feminist biologically theories which posit that, biologically, there is too little difference in human bodies to justify the classification of two sexes.
B) Modern Western notions of sex and gender which sees all human beings as having only one sex, female or male.
C) Pre-modern notions of sexual anatomy, like the ideas of Aristotle and Galen, who saw female anatomy as the same as male anatomy, just inverted.
D) A social critique of contemporary built environments which are built to suit the average male body.