What might a malfunction in the landing gear system cause?

A malfunction in the landing gear system can indeed lead to a failure to deploy the landing gear. This is a critical safety issue, as the landing gear is essential for providing a stable platform for landing and taking off. If the system experiences a failure, whether due to hydraulic issues, electrical malfunctions, or mechanical problems, the landing gear may not extend or lock into place. This situation can pose a significant risk during landing, as the aircraft may have to land without the proper landing configuration, potentially resulting in damage to the airframe and jeopardizing the safety of the passengers and crew.

The other options suggest potential issues related to flight dynamics or operational limitations but do not directly correlate with the functions of the landing gear system. For example, while longer landing distances can be a concern in various scenarios, it is not a direct consequence of a landing gear malfunction like failure to deploy is. The option regarding flight altitude does not relate to landing gear issues at all, and reduced control surface effectiveness pertains to different aspects of flight control. Thus, the correct answer is clearly tied to a fundamental role of the landing gear in aviation safety.