A biped animal is a terrestrial animal that move about with the help of its two rear limbs. An example of this is ostrich. A quadruped animal is a terrestrial animal that uses four limbs for locomotion. An example of this is cat. Other examples are deer, zebra, wolf, etc. Thus, for the analogy given in the question, the correct matches are as follows: Biped : quadruped : Ostrich : CAT.