A : Intensity of sound wave does not change when the listener moves towards or away from the stationary source .
R : The motion of listener towards a stationary source causes an apparent change in wavelength of sound .

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. Both 'A' and 'R' are false

Answer

B