Pneumonia is usually caused by a bacterial or viral infection in the , which causes the patient to cough up yellow-green mucus.

Explanation:

Pneumonia is tissue inflammation in the longs, which is caused by a bacterial infection. When that happens, the system begin to make the person cough, as a reaction to expelled the external particles or organisms that are causing the problem.

are there any letter choices to this or is this an open ended question?

answer; (b) temporal///frontal;