In which of the following do the groups exhibit a +M effect when attached to a benzene ring?

A $- NHCOCH X_{3}$
B $- CH X_{3}$
C $- OCH X_{3}$
D $- Cl$

Answer: A, C, D

- NHCOCH X_{3}

- OCH X_{3}

and

- Cl

each have a lone pair on the atom bonded to the ring that can be donated into the pi system (+M). The methyl group has no lone pair or pi bond. It acts through +I and hyperconjugation.

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In which of the following do the groups exhibit a +M effect when attached to a benzene ring?

Answer: A, C, D

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