Which of the following is typically considered a safety-critical component in aircraft?

Landing gear is indeed a safety-critical component in aircraft due to its essential role in both takeoff and landing operations. It supports the aircraft's weight during ground operations, provides stability during taxiing, and absorbs the impact during landing. The structural integrity and functionality of landing gear are paramount; if it fails, it can lead to catastrophic accidents.

In contrast, the other options, while important for comfort and functionality, do not directly impact the aircraft's operational safety in the same way. Interior panels, seat covers, and cabin lighting enhance passenger experience but are not critical to the aircraft's ability to safely fly or land. Therefore, landing gear stands out as a component that must meet rigorous safety standards and undergo extensive testing to ensure reliability in critical flight situations.