What general restriction applies to the practice of falconry regarding firearms?

The correct answer reflects the strict regulations surrounding the practice of falconry, which prohibits all use of firearms, particularly when a falconer is hunting with their bird. This restriction is in place to ensure the safety of the bird and to promote ethical hunting practices. The emphasis is on using the bird's natural hunting skills rather than relying on weapons, which maintains the integrity of the sport and encourages more traditional methods of hunting.

The prohibition on firearms helps to prevent any potential misuse or accidents that could arise from their use during falconry activities, ensuring that the focus remains on the bird of prey. Falconry is a sport that emphasizes a close bond between the falconer and the bird, requiring trust and skill without the interference of firearms.

The other choices suggest circumstances where firearms might be permissible, but they do not align with the regulations that prioritize the safety and well-being of both the birds and the environment in which falconers operate.