Multi-choice problem: Continue writing the next sentence in this paragraph:

How to protect your dog around backyard pools
Teach your dog to swim.
Not every dog knows how to swim. Many owners assume that their dogs know how to swim so they don't worry about them around pools.

Choose from:
[a]. However, making this assumption can help you get the dog to do so more easily. Do several different activities so that the dog can learn how.
[b]. Dogs may be inexperienced and not know how to swim. They also may panic and not swim correctly.
[c]. Therefore, you don't know exactly how to get your dog to swim. Therefore, it's important to practice.
[d]. However, taking time to train your dog will help him, too. Take out the proper swimming pieces before you go swimming to prevent splashing.
[b].