(A) : Infrared waves are often called heat waves. (R) : Infrared waves, invole vibrations of electrons, atoms or molecules of a substance. This increases the internal energy of the substance.

Options

A. Both 'A' and 'R' are true and 'R' is the correct explanation of 'A'.
B. Both 'A' and ’R' are true and 'R' is not the correct explanation of 'A
C. A' is true and 'R' is false
D. 'A' is false and R' is true

Answer

A