Final answer:
In situations where aircraft are converging at the same altitude, helicopters are typically required to give way to airplanes due to their enhanced maneuverability.
The correct answer is a.
Step-by-step explanation:
When two aircraft are converging at approximately the same altitude, the right-of-way rules determine which aircraft should give way. The question focuses on interaction between different types of aircraft such as gliders, aeroplanes, and helicopters. According to the aviation regulations in most places, powered aircraft should give way to non-powered aircraft, and among powered aircraft, airplanes generally have the right-of-way over helicopters. Because of their ability to maneuver more easily, helicopters shall give way to airplanes. However, specific circumstances can affect these general rules, such as the performance of the aircraft or whether one is in distress.