Which bacteria is primarily responsible for gonorrhea?

The bacteria primarily responsible for gonorrhea is Neisseria gonorrhoeae. This organism is a gram-negative diplococcus that specifically infects mucous membranes and is known to cause the sexually transmitted infection gonorrhea. It can affect various areas of the body, including the genital tract, rectum, and throat, leading to symptoms such as painful urination and discharge.

Understanding the other options is useful in context. Chlamydia trachomatis is responsible for chlamydia infections, which is another type of sexually transmitted infection but distinct from gonorrhea. Escherichia coli is typically associated with gastrointestinal infections and is not related to sexually transmitted infections. Streptococcus pneumoniae is known for causing pneumonia and other respiratory infections, not gonorrhea. Hence, Neisseria gonorrhoeae is the definitive answer for the causative agent of gonorrhea.