Final answer:
Coitus interruptus, also known as the withdrawal method, is a relatively ineffective method of birth control due to its high failure rate.
The answer is option ⇒b
Step-by-step explanation:
The relatively ineffective method of birth control known as coitus interruptus is the withdrawal method, where a man withdraws his p`enis from his partner's vagina before ejaculation occurs. This method has a high failure rate because of the possibility of sperm in the pre-ejaculate that can lead to pregnancy.
To arrange the methods of contraception in order of typical effectiveness from least to most effective: fertility awareness method, withdrawal, male co`ndom, and IUD.
With regards to effectiveness, a contraceptive method with a 35 percent failure rate would not be considered effective, because it means that 35 out of 100 couples using this method would potentially conceive over the course of a year.
The answer is option ⇒b