An observer moves towards a stationary source of sound with a speed $1/5^{th}$ of the speed of sound. The wavelength and frequency of the source emitted are $\lambda$ and $f$ respectively. The apparent frequency and wavelength recorded by the observer are respectively :

Question

( A ) f, 1.2$\lambda$
( B ) 1.2f, 1.2$\lambda$
( C ) 0.8f, 0.8 $\lambda$
( D ) 1.2f, $\lambda$