Give scientific reasons :
Though tortoise lives on land as well as in water, it cannot be included in class- Amphibia.

Explanation

i.Tortoise creeps on land as it cannot lift its body up.
ii. Unlike amphibians, the skin of tortoise is dry and scaly.
iii. Neck is absent in amphibians but in tortoise, neck is present between the head and trunk.
iv. The digits of tortoise have claws, which are absent in amphibians.
Thus, tortoise cannot be included in class- Amphibia, though it lives on land as well as in water and is included in class Reptilia.