What is a common source of issues related to cabin air quality?

A dirty or clogged cabin air filter is indeed a common source of issues related to cabin air quality. The cabin air filter is responsible for trapping dust, pollen, and other airborne pollutants before they enter the passenger compartment. Over time, this filter can become saturated with contaminants, leading to reduced airflow and allowing harmful particles to circulate within the cabin. This can not only diminish the comfort of the occupants but can also negatively impact health, particularly for those with allergies or respiratory conditions. If the filter is not replaced or cleaned regularly, it can cause unpleasant odors and limit the effectiveness of the heating and cooling systems, further affecting the overall air quality inside the vehicle.

While other options may pose their own sets of issues, a clogged cabin air filter specifically targets the air quality aspect in a direct way, making it the most relevant choice for this question.