Which STD is responsible for the appearance of a chancre, a small, painless, reddish-brown sore on the mouth or on the sex organs?

Which STD is responsible for the appearance of a chancre, a small, pai

1.	Which STD is responsible for the appearance of a chancre, a small, painless, reddish-brown sore on the mouth or on the sex organs?
Answer» Which STD is responsible for the appearance of a chancre, a small, painless, reddish-brown sore on the mouth or on the sex organs?