Which of the following animal lays an unfertilized egg?
Rana
The animals in which fertilization is external lay unfertilized eggs. Amphibians and Fishes lay unfertilised eggs. Rana is a genus name of a frog, which shows external fertilization. So correct answer is Rana.
Pteropus is a genus of bats, which is a viviparous mammal.
Naja is a genus of snakes commonly referred to as cobras. The fertilization in snakes is internal and hence they lay fertilized eggs.
Duck-billed platypus is an egg-laying mammal and it lays fertilized eggs.