What is the number of animals, amongst the animals given below, that have both a four-chambered heart and endothermy?
Crocodilus, Aptendytes, Canis, Calotes, Struthio, Delphinus, Testudo, Ichthyophis
| 1. | 3 | 2. | 4 |
| 3. | 5 | 4. | 6 |
| 1. | Amphibians, Reptiles, and Birds |
| 2. | Crocodiles, Birds, and Mammals |
| 3. | Crocodiles, Lizards, and Turtles |
| 4. | Lizards, Mammals, and Birds |
| 1. | Metamerism appeared for the first time in annelida |
| 2. | Arthropods have jointed appendages and chitinous exoskeleton |
| 3. | Reptiles are endotherms |
| 4. | Forelimbs of birds are modifies into wings |