What are the measures one has to take to prevent contracting $STDs$?

$A$ : Diseases or infections which are transmitted through sexual intercourse are collectively called sexually transmitted diseases $(STDs)$.
$R$ : $STDs$,if not properly treated,may lead to pelvic inflammatory diseases,abortion,stillbirth,ectopic pregnancies,infertility,or even cancer of the reproductive tract.

Following are infection sites for syphilis, $EXCEPT$

Identify the sexually transmitted disease caused by bacteria.

All reproductive tract infections $(RTIs)$ are $STDs$,but all $STDs$ are not $RTIs$. Justify with an example.

Define the location and function of the following: Copper-$T$ and Neisseria gonorrhoeae.