Solution
$\nu = \frac{{v + {v_o}}}{{v - {v_s}}}{\nu _0}$
Where, vs and vo are with respect to the medium.
If wind blows from observer to the source,
${f_2} = \frac{{V + u - w}}{{V - (u + w)}}{f_1}$
${f_2} > {f_1}$
If wind blows from source to the observer,
${f_2} = \frac{{V + u + w}}{{V - (u - w)}}{f_1}$
${f_2} > {f_1}$
Hence, (A) & (B).