Final answer:
A diaphragm functions by covering the cervix to prevent sperm from entering the uterus, typically used with spermicide and left in place for several hours after intercourse. It has a 12% failure rate and doesn't protect against STIs.
Step-by-step explanation:
The correct option : a
A diaphragm is a barrier method of contraception that is inserted vaginally and must be placed over the cervix to prevent sperm from passing into the uterus. It is often used with spermicide to enhance its effectiveness. The diaphragm should be left in place for at least six hours after intercourse to ensure that sperm are prevented from reaching the egg, thus avoiding pregnancy. This method has a typical-use failure rate of about 12 percent, which is lower than that of condoms but still presents a significant chance of pregnancy. During use, diaphragms may be associated with an increased risk of urinary tract infections, and they do not protect against sexually transmitted infections (STIs).
Using a diaphragm is a form of barrier method of contraception, which means it physically blocks the sperm from reaching the egg, preventing fertilization and pregnancy.