Final answer:
A basket muzzle is the type of muzzle that allows a canine to open its mouth and can be worn for long periods if needed.
Step-by-step explanation:
The correct answer is A. Basket muzzle. A basket muzzle is a type of muzzle that allows a canine to open its mouth and pant, which is important for cooling off and socializing. It has a basket-like structure made of wire or plastic that covers the dog's mouth, while still allowing them to breathe and drink water. Basket muzzles are designed to be safe and comfortable for dogs to wear for long periods if needed, which is why they are commonly used in veterinary clinics, grooming salons, and other professional settings.