When conducting maneuvers at night, which of the following is strictly prohibited?

Engaging in aerobatics and intentional spins at night is strictly prohibited due to significant safety concerns associated with reduced visibility and the inherent risks involved. At night, pilots have a limited ability to perceive their surroundings and gauge altitude, making it much more difficult to execute complex maneuvers safely. Aerobatics often require a clear sight of references on the ground and the horizon, which are difficult to identify at night. Additionally, recovering from intentional spins is more challenging in low-light conditions, and a loss of situational awareness can lead to severe accidents. Therefore, to ensure the safety of flight operations during nighttime, these maneuvers are not allowed.

The other options, while they may have their own risks, do not carry the same level of prohibition as aerobatics and intentional spins. Practicing emergency landings, for instance, is an important skill that can be safely executed with the right preparation and training, even at night. As for low-level navigation and formation flying, there are regulations and guidelines in place to conduct these safely, provided they are performed with caution.