Q. All mammals without any exception are characterized by
A) Viviparity and biconcave red blood cell
B) Extra abdominal testis and four-chambered heart
C) Heterodont teeth and 12 pairs of cranial nerves
D) A muscular diaphragm and milk producing glands
Explanation
In mammals the teeth are heterodont (i.e., consists of incisors, canines, premolar and molars) thecodont (in sockets of jaw bones). The brain has 12 pair of cranial nerves.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.