Question

The character which differentiates mammals from birds is

• A. Seven cervical vertebrae
• B. Parental care
• C. One aortic arch
• D. Metanephric kidney

Answer 1

The correct option is A Seven cervical vertebrae

Almost all mammals have 7 cervical vertebrae but birds have 13 to 25 cervical vertebrae.

Birds and mammals are both known for their parental care in their own nests and shelters.

Both groups have one aortic arc.

Metanephric or fully mature kidneys can also be seen in birds as well as mammals.

So the correct answer is 'Seven cervical vertebrae'.