Q: Rising and falling levels of what will result in progression of the ovarian and menstrual cycles?


Read this paragraph and choose the correct option from the provided answers:

Figure 43.17 Rising and falling hormone levels result in progression of the ovarian and menstrual cycles. (credit: modification of work by Mikael Häggström).

 Choices:

- red blood cells

- oxygen

- blood pressure

- hormones


A:
hormones