21- Ape Corporation owns 85% of Bird Corporation and 90% of Cat Corporation. Bird Corporation owns 79% of Eel Corporation and 60% of Dog Corporation. Cat Corporation owns 30% of Dog Corporation. All corporations are domestic C corporations having a single class of stock outstanding. Which corporations form a controlled group for federal income tax purposes? C Ape, Bird. Ape, Bird, Cat. Ape, Bird, Cat, Dog. O Ape, Bird, Cat, Dog, Eel