What is the function of Copper-$T$?

Oral contraceptives inhibit $A$ and implantation as well as the quality of cervical $B$ to prevent the entry of sperms. Choose the correct option for $A$ and $B$ to complete the given statement.

Find out the correct aspects of lactational amenorrhoea.
$I$. Ovulation does not occur during the lactational period.
$II$. Chances of the failure of contraception are almost nil up to six months following parturition.
$III$. Side effects are almost nil.
$IV$. It is a natural method of contraception.
$V$. It increases phagocytosis of sperms.

Regarding the given diagram,choose the incorrect statement $:-$

Which of the following is a method for birth control?

Which of the following can be used by females as injections or implanted under their skin?