Question

Crocodile and penguin are similar to whale and dogfish, in which one the following features?

• A. Possess a solid single stranded central nervous system
• B. Lay eggs and guard them till they hatch
• C. Possess bony skeleton
• D. Have gill slits at some stage

Answer 1

The correct option is D Have gill slits at some stage

Dogfish is a family of sharks, which are marine animals possessing gills slits.
Crocodile and penguins are vertebrates and all vertebrates at some stage of their life possess gill slits in the pharyngeal region. Thus, the correct answer is D.