Select the word-pair in which the two words are related in the same way as are the two words in the following word-pair.

Toad : Amphibian

Tortoise : Reptile

Logic here is :

Toad : Amphibian

Toad belongs to the class amphibian.

Similarly ,

By observing all option only option 4 go with this logic .

Tortoise : Reptile

Tortoise belongs to the class of Reptile .

Tortoise : Reptile is correct answer .