The correct option is
B between the uterus and the vagina
The opening of the uterus body is called the cervix. It joins the uterus to the vagina in the female body. The cervix communicates with the uterus with the help of an opening called an internal orifice and communicated with the vagina with the help of an external orifice.
Thus, the correct answer is 'Between uterus and vagina'.