What is the most common bacterial sexually transmitted infection, which left untreated can lead to pelvic pain, pelvic inflammatory disease, infertility, or ectopic pregnancy?
a. chlamydia
b. herpes
c. hpv
d. syphilis

The right answer is Chlamydia (it is the one which is associated with these symptoms).

When Chlamydia germs cross the vagina, then the cervix to reach the fallopian tubes, even the ovaries, it is a pelvic inflammatory disease.

We also talk about salpingitis, when the infection affects the trunk.

Chlamydia infections mainly affect young people between the ages of 15 and 25. The infection is formidable because it can evolve long without the slightest symptom. However, there is a real risk of tubal infection (salpingitis) with the risk of infertility that entails, as well as an increased risk of ectopic pregnancy.

I believe the correct answer is Chlamydia

Chlamydia is a sexually transmitted infection that affects many body organs but the one mostly affected is the reproductive system and the urinary tract that form the genitourinary tract e.g. the urethra. The disease is caused by the bacteria called Chlamydia spp. and the one that is directly implicated with the disease is Chlamydia trachomatis. It affects females more because of the increased surface area of the vagina.

The bacteria is introduced in the vagina through unprotected sex from an infected person and infect the squamocolumnar epithelial cells which are the simple cells that line the organs of the genitourinary system. When left untreated, the bacteria will move up the vagina into the cervix and the uterus and simultaneously also into urethra towards the bladder via the ureters. The body will then react to the infection by inducing a process called inflammation to try to kill the bacteria. Inflammation is a combination of the following properties:

When the bacteria reaches the fallopian tubes, it will trigger inflammation which will block the oviduct, become painful causing the pelvic pain and blocking eggs from being fertilized as they head to the uterus. This will force implantation to happen in the fallopian tubes causing the dangerous condition known as ectopic pregnancy. Treatment is via use of antibiotics. Its complications when left untreated include conjuctivis and pneumonia when it invades the lungs via the bloodstream.

Level: High School

Subject: Biology

Topic: Reproductive System

the correct answer is 2 and 4

if you know your abc's you should be able to get your answer or just use google