Chances are, the primary lesions are caused by
A) Neisseria gonorrhoeae.
B) Treponema pallidum.
C) Plasmodium vivax.
D) Salmonella typhi.

Hint:Syphilis is the after effect of a contamination of the genital tract by the bacterium. If not treated they may cause damages to organs like heart and brain.

Complete answer:
Syphilis is a contagious disease which is mainly spread through sexual activity. It is a bacterial disease and it starts as a painless sore generally on the genitals. And also it spreads through skin or mucous membrane contact with these sores. Syphilis is a disease that can cause genuine medical conditions in the event that it isn't dealt with.

Syphilis is isolated into stages (primary, secondary, latent, and tertiary). There are various signs and manifestations related to each stage. You can get syphilis by direct contact with a syphilis sore during vaginal, anal, or oral sex. You can discover injuries nearby the penis, vagina, or butt, or in the rectum, on the lips, or in the mouth. Syphilis can spread from a tainted mother to her unborn baby.

An individual with primary syphilis for the most part has a sore or wounds at the first site of disease. These bruises for the most part happen close by the privates, around the anus or in the rectum, or in or around the mouth. These injuries are ordinarily (however not generally) firm, round, and easy. Secondary syphilis incorporate skin rash, swollen lymph hubs, and fever. The signs and manifestations of primary and secondary syphilis can be mellow, and they probably won't be taken note. During the latent stage, there are no signs or manifestations. Tertiary syphilis is related to extreme clinical issues.The bacteria which cause syphilis are called Treponema pallidum.

Hence, the correct answer is option ‘B’.

Note:Syphilis is one sort of sexually transmitted disease brought about by the bacterium, Treponema pallidum. Syphilis is passed starting with one individual then onto the next during direct sexual contact with an essential syphilis injury brought about by bacteria. The mucocutaneous injuries harbours the microbes.