Read the following paragraph carefully and cross out the sentence which breaks unity. 1 There are many types of pets in an average household. 2 People will often even choose pets according to their personalities. 3 Some people like small dogs that are easy to take care of and do not demand a lot of attention. 4 Some owners prefer strong or vicious dogs, like bulldogs for example. 5 Other people might like cats because they are independent and really need no attention at all. 6 Birds provide people with a lot of company, if you like bird songs, but their cages need a lot of cleaning. 7 A fish tank is great to look at but the tanks must be cleaned often as well. 8 Some people even treat their plants like pets and talk to them. 9 In a zoo, large animals, like polar bears, are left to themselves in their cages.