Question

Select the option which shows viviparous animals only.
a. Lizard, Turtle
b. Platypus, Crocodile
c. Cow, Crocodile
d. Whale, Mouse

Answer 1

Hint: As we know that viviparous animals are those animals which directly give birth to their young ones whereas the oviparous animals are those that lay eggs first and then hatch these eggs resulting into their young ones and ovoviviparous animals are those that can give birth to young ones as well as can lay eggs.

Complete answer:
We have already discussed that animals can be categorized into three main classes, the first one is viviparous animals which are those animals that directly give birth to their young ones, the second one is oviparous animals which are those that lay eggs first and then hatch these eggs resulting into their young ones and lastly the ovoviviparous animals which are those that can give birth to young ones as well as can lay eggs.

In viviparous animals, the zygote is developed inside the body of the mother and then after maturation of these zygotes into a fully developed young one, these are delivered outside and their chances of survival are more as compared to the oviparous animals. Because their eggs are prone to accidents and predators.

So viviparous animals include mammals like whale, shark, mouse, humans etc. except some egg-laying mammals like Platypus.

Lizards and turtles both lay eggs and hatch them until the birth of their young ones. Similar is the case of crocodiles. Therefore these are the oviparous animals.

Hence, the correct answer is option (d).

Note: The characteristic feature of mammals is the presence of mammary glands to nourish their young ones which are directly given birth but Platypus although a semi-aquatic mammal is the exception in mammalia class because it is the only mammal that lays eggs.