Write the next sentence in the following story.

How to stop your cat from attacking your dog
Get a cat tree.
A cat tree will provide your cat a safe haven from the attentions of your dog. Cats often attack dogs to get the dog to leave them alone, so providing a spot where your cat can nap in peace is essential for maintaing good pet relations.

Choose from: [I] Many options for cat trees include baby trees, baskets, or large boxes that cats can climb and hide in. Make sure you have a carrier big enough for your dog to sleep and get out whenever she needs it. [II] Place the cat tree in an area that is often frequented by both pets so that the cat can choose to climb to its hiding spot instead of attacking the dog. Make sure that the dog can't get to the cat when it's in the cat tree. [III] Resist the urge to run away if your cat starts growling. If your cat begins growling with intent to attack your dog, that is a sign that it is taking its aggression out on your pet. [IV] If your house does not provide a cat tree, buy a box or scrap of cardboard that is cat sized and easy to turn. You will be able to turn the cardboard so that its top is the most visible by your cat.. The answer should be
[II]