Which of the following animals can only belong to one category and meet the following conditions: (1) if animal B is not a bird, then animal A is a mammal (2) or animal C is a mammal, or animal A is a mammal (3) If animal B is not a bird, then animal D is not a fish (4) or animal D is a fish, or animal E is not an insect (5) if animal E is not an insect, then animal B is not a bird. Which of the following, if true, can conclude that "Animal C is a mammal"? ['Animal D is not a fish.', 'Animal E is an insect.', 'Animal B is not a bird.', 'Animal A is a mammal.']