Abstinence is the only birth control method that has a zero percent failure rate for an unplanned pregnancy and 100 percent rate of protection against stis. true or false

The question is asking whether it is true that abstinence is the only birth control method that has a zero percent failure rate for an unplanned pregnancy and 100 percent rate of protection against STIs. This is true. Abstinence, if it can be maintained, means that there is no risk at all because there is no genital contact between the people involved, Other methods, for example condoms, are also quite reliable but none have a 100 percent success rate in preventing STIs and pregnancy.

Can you explain it well?