Which of the following is a common cause of residential fires?

Faulty electrical wiring is a well-documented and common cause of residential fires. Electrical systems that are improperly installed, outdated, or damaged can lead to short circuits, overheating, or sparks, all of which can ignite surrounding materials and start a fire. This risk is particularly significant in older homes where wiring may not meet current safety standards or has been subjected to wear and tear over time.

In contrast, thunderstorms, high humidity, and low outdoor temperatures do not directly cause fires. While thunderstorms can lead to lightning strikes that may ignite structures or create other hazards, they are not a frequent or direct cause of residential fires like electrical issues are. High humidity and low temperatures generally do not contribute to fire risks within homes; instead, they can affect other environmental factors but do not have a causative role in fire events.