Phenol undergoes electrophilic substitution more easily than benzene because: A) –OH group exhibits +M effect and hence increases the electron density on the o- and p- positions. B) Oxocation is more stable than the carbocation. C) Both (a) and (b)D) –OH group exhibits acidic character.

The correct answer is A) –OH group exhibits +M effect and hence increases the electron density on the o- and p- positions.

Phenol (C6H5OH) contains a hydroxyl group (-OH), which has a lone pair of electrons. This lone pair can delocalize into the benzene ring through resonance, creating a partial positive charge on oxygen. This leads to the donation of electron density to the ortho and para positions of the benzene ring, making them more nucleophilic and thus more susceptible to electrophilic substitution reactions. This phenomenon is known as the "+M effect".

Option B is incorrect because the stability of the oxocation formed during the electrophilic substitution reaction isn't the primary reason for phenol's increased reactivity compared to benzene.

Option D is incorrect because although phenol does exhibit acidic character due to the presence of the -OH group, it's not directly related to its increased electrophilic substitution reactivity.