Final answer:
A vasectomy is not a hormonal method but a form of surgical sterilization for men, whereas post-coital contraception, vaginal ring, and injectable contraceptive are all hormonal methods that prevent pregnancy.
Step-by-step explanation:
Of the following contraceptive methods, which is NOT a hormonal method? The answer is D. vasectomy. This is because a vasectomy is a surgical procedure used as a sterilization method for men, where the vas deferens are sealed to prevent sperm from entering the ejaculate and thereby preventing fertilization. In contrast, post-coital contraception (A), vaginal ring (B), and injectable contraceptive (C) are all based on the administration of hormones to prevent pregnancy.
Hormonal methods are typically more effective than barrier methods such as condoms or diaphragms. Likewise, an intrauterine device (IUD) can be a highly effective form of reversible contraception when compared to options like withdrawal or tubal ligation, which are either less effective or irreversible.
Understanding and choosing the right contraceptive method is critical for effective pregnancy prevention and requires considering factors such as adherence, personal health, and whether short-term or permanent prevention is desired.