What constitutes a situation where a pilot is responsible for avoiding hazards during flight?

A pilot is responsible for avoiding hazards during flight primarily through the obligation to maintain situational awareness concerning other aircraft, terrain, and various obstacles regardless of the airspace controlled or uncontrolled. This responsibility is fundamentally rooted in a pilot's duty of care to ensure safety.

In practice, avoiding other traffic includes being vigilant about the positions of other aircraft, maintaining safe distances, and being aware of traffic patterns and potential converging paths. This also extends to terrain clearance, where a pilot must ensure they are flying at a safe altitude above obstacles and terrain to prevent collisions. Such awareness is essential not only for the safety of the pilot but for the safety of all in the vicinity.

The other choices do not encapsulate the complete scope of a pilot’s responsibilities. For instance, flying above 10,000 feet does not inherently change the pilot's obligations regarding hazard avoidance. Similarly, requesting VDF steer is a navigation aid that helps gain situational awareness but does not replace the fundamental responsibility of avoiding hazards. Lastly, while the rules in controlled airspace might impose certain responsibilities, the obligation to avoid hazards applies universally, not just in controlled airspace. Therefore, the correct choice highlights the comprehensive responsibility of pilots to avoid hazards during all phases of flight.