Where must registration numbers and stickers be displayed on snowmobiles?

Registration numbers and stickers must be displayed on both sides of the cowling of snowmobiles to ensure they are visible from either side of the vehicle. This allows for easy identification and compliance with local regulations, as they are designed to be clearly legible to enforcement personnel and other users on the trails or waterways. Proper display of registration numbers is crucial not only for legal purposes but also for safety, as it helps in identifying the owner in case of an emergency or theft.

The other options involve placements that may not meet the legal visibility requirements. For example, displaying numbers solely on the rear of the vehicle, the front bumper, or underneath the seat would hinder visibility and could lead to potential legal issues or fines for non-compliance with registration laws. Therefore, the correct practice is to adhere to the specified placement on both sides of the cowling.