[A]: Mesozoic era is known as the 'Age of Reptiles'.
[R]: It was the era of origin, differentiation and final extinction of dinosaurs which thrived in sea, in air and on land.

Options

A. If both A and R are true and R is the correct explanation of A
B. If both A and R are true but R is not the correct explanation of A
C. If A is true and R is false
D. If both A and R are false

Answer

A