Which of the following disease can be caused by a bacterium?

Among the given options, syphilis is the disease that can be caused by a bacterium. Syphilis is a sexually transmitted infection caused by the bacterium Treponema pallidum. It is usually spread through sexual contact, but can also be passed on from mother to child during pregnancy or childbirth. The symptoms of syphilis can vary widely, but usually, the infection progresses through several stages, including the development of a painless sore or ulcer at the site of infection, followed by a rash, fever, and swollen lymph nodes. If left untreated, syphilis can cause serious complications, such as damage to the heart, brain, and other organs. Ringworm is caused by a fungal infection, while poliomyelitis is caused by a virus. Malaria is caused by a parasite that is transmitted through the bite of infected mosquitoes.