Im pretty sure is the last one
Differences in strength, hormones, body structure, bone structure. Like when you draw a man figure, the body is usually a rectangle but when you draw a female, the body is an upside down triangle. Hormones like estrogen, only women have. Similarities are intelligence, appearance. Women and Men are treated differently, especially in the work place, because they used to be seen as lower class and we are thought of not being able to do some of the obs that men do, like manual labor because women don't have the same muscle mass or upper body strength as men do but men are also seen as not being able to do some jobs that women do, especially in households, because they don't have motherly instincts or they can't cook as well as women can.
