How an — OH group attached to carbon in the benzene ring activates benzene towards electrophilic substitution ?

How an — OH group attached to carbon in the benzene ring activates benzene towards electrophilic substitution ?
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The lone pair of electrons present on oxygen atom enter into resonance with the benzene ring. As a result, the electron density becomes higher at o- and p- position and due to higher electron density, the ring gets activated towards electrophilic substitution.

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