Which system is responsible for pulling stale air out of kitchens and bathrooms?

The correct choice is ventilation, as it refers specifically to the system designed to exchange indoor air with outdoor air to maintain air quality. In kitchens and bathrooms, where moisture and odors are often generated, ventilation systems actively work to remove stale air, helping to prevent issues like mold growth and ensuring a healthier living environment.

A filtration system primarily focuses on cleaning the air by removing particles and contaminants, but it does not necessarily exhaust stale air from a space. Similarly, a heating system's primary function is to provide warmth, and while it may contribute to air circulation, it does not specifically address stale air removal. The cooling system is designed to lower temperatures and may involve air circulation, but its role is not directly related to the removal of stale air in kitchens and bathrooms. Thus, ventilation is the designated system for this purpose, emphasizing the importance of air exchange in maintaining indoor quality.