One of the methods of birth control is?

The correct option is A. Abstaining from coitus (sexual intercourse) during the fertile period of the menstrual cycle (approximately days 10-17) is a method of birth control known as the rhythm method or calendar method. This method relies on avoiding intercourse during the time when ovulation is most likely to occur, thus reducing the chance of fertilization. The other options are incorrect: B is incorrect because ejaculation during coitus does not prevent pregnancy; C is incorrect because abortion is the termination of a pregnancy, not a method of birth control; D is incorrect because artificial insemination is a method of assisted reproduction, not birth control.