आजकल वर्गीकरण किस आधार पर किया जाता है ?
A. Presence and absence notochord
B. Similarities in external features
C. Breeding habits
D. Anatomical and physiological characteristics
A. Presence and absence notochord
B. Similarities in external features
C. Breeding habits
D. Anatomical and physiological characteristics
Correct Answer – B