What is the function of copper ions in copper-releasing $IUDs$?

$ . . . . . . $ is a natural contraceptive method.

Diaphragms are contraceptive devices used by females. Choose the correct option from the statements given below:
$i$. They are introduced into the uterus
$ii$. They are placed to cover the cervical region
$iii$. They act as physical barriers for sperm entry
$iv$. They act as spermicidal agents

$A$ contraceptive pill contains:

$A$: Lactational amenorrhoea is one of the natural methods of birth control.
$R$: High levels of prolactin inhibit the secretion of gonadotropins.

The action of contraceptives is to: