Why is the activating effect of `-NHCOCH_3` group in the above reaction less than the activating effect of amino group?

Options

A. Due to mesomeric effect of benzene ring.
B. Due to inductive effect of alkyl group.
C. Due to resonance effect of acetanilide.
D. All of the above.

Answer

C

Explanation

The lone pair of electrons on nitrogen of acetanilide interacts with oxygen alom due to resonance as shown below :

Hence, the lone pair of electrons on nitrogen is less available for donation to benzene ring by resonance. Therefore, activating effect of `NHCOCH_3` group is less than that of amino group.