Hey there Serina!
Your correct answer to this question would be (Human chorionic gonadotropin). As when a women is not pregnant, she would contain estrogen, progesterone, testosterone, and also, follicle-stimulating hormone. These are natural when coming to a women, and her periods, this is something that she would always contain, but when this women is pregnant, she would contain chorionic gonadotropin which is not normal, when not pregnant.
Hope this helps you well!