Which of the following belongs to $+\mathrm{I}$ group?

$+\mathrm{I}$ Group is electron releasing. The charge is transmitted across a chemical compound's chain when it wants to liberate electrons, like when an alkyl group is added to a hydrocarbon chain. The Positive Inductive Effect, often known as the +I Effect, is this effect.

For instance, the methyl group linked to the carboxylic acid group makes formic acid (HCOOH) more acidic than acetic acid (CH3 COOH) due to the +I inductive effect.

From the given option, only  ${\mathrm{CH}}_3$  has a propensity to emit electrons. As they have a propensity to be received favourably by I groups, $-\mathrm{OH}, -{\mathrm{OCH}}_3$, and $-\mathrm{COOH}$ refer to these groups as I.