What health issue is commonly caused by spherical bacteria?

Pneumonia is commonly caused by spherical bacteria, known as cocci. One of the most well-known bacterial causes of pneumonia is Streptococcus pneumoniae, which is a spherical (coccus) bacterium and a leading pathogen responsible for community-acquired pneumonia. This type of bacteria can multiply in the lungs, leading to inflammation and the accumulation of fluid, which are key characteristics of pneumonia.

In the context of other health issues mentioned, influenza is primarily caused by viruses rather than bacteria. Tuberculosis is typically associated with rod-shaped bacteria called Mycobacterium tuberculosis. Bronchitis can be caused by either viral or bacterial infections but is not specifically linked to spherical bacteria; rather, it can arise from a variety of bacterial forms. Thus, pneumonia is distinctly connected to spherical bacteria, making it the correct choice among the options provided.