Go through the following flow chart for division of subphylum vertebrate. Fill the graph A, B, C and D and select the correct option.

Options

A. `{:(A,B,C,D),("Ostracodermi","Cyclostomata","Pisces","Tetrapoda"):}`
B. `{:(A,B,C,D),("Cyclostomata","Ostracodermi","Pisces","Tetrapoda"):}`
C. `{:(A,B,C,D),("Ostracodermi","Tetrapoda","Cyclostomata","Pisces"):}`
D. `{:(A,B,C,D),("Pisces","Ostracodermi","Tetrapoda","Cyclostomata"):}`

Answer

A

Explanation

Subphylum Vertebrata is divided into two divisions. They are agnatha (jawless) and gnathostomata (with jaw). Agnatha are extinct and Cyclostomata (e.g., hag fish). Jawed vertebrates are divided into two superclasses-Pisces (true fish) and Tetrapoda (four limbs).