Which of the following is an $STD$?

Chancroid is a sexually transmitted disease caused by:

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

From the sexually transmitted diseases mentioned below,identify the one which does not specifically affect the sex organs.

$STDs$ can be considered as self-invited diseases. Comment.

Select the correct option for the early symptoms of Sexually Transmitted Diseases (STDs).
$I -$ Itching in the genital area
$II -$ Abortion
$III -$ Fluid discharge in the genital area
$IV -$ Pelvic Inflammatory Diseases $(PID)$
$V -$ Slight pain in the genital area
$VI -$ Swelling in the genital area