Choose the word that is a necessary part of the underlined word.
vertebrate

A. backbone

B. reptile

C. mammal

D. animal

Answer: Option A

Solution(By Examveda Team)

All vertebrates have a backbone. Reptiles (choice b) are vertebrates, but so are many other animals. Mammals (choice c) are vertebrates, but so are birds and reptiles. All vertebrates (choice d) are animals, but not all animals are vertebrates.