Amongst the following methods of contraception,which can be regarded as the most cost-effective and easily reversible method of contraception?

In vasectomy, a small part of the $vas \text{ } deferens$ is removed through a small incision on the scrotum.

Which of the following is incorrect regarding vasectomy?

What is true about 'Saheli'?
$I$. Developed at $CDRI$,Lucknow
$II$. Contains a steroidal preparation
$III$. 'Once-a-week' pill
$IV$. Many side effects
$V$. High contraceptive value
$VI$. Very few side effects
$VII$. Low contraceptive value

Which organization developed the spermicide 'Saheli' (or related contraceptive research)?

These methods of birth control are highly effective,but their reversibility is very poor.