Which is the correct order of stability of the para-substituted benzyl cations $p - X - C X_{6} H X_{4} - CH X_{2} X^{+}$ ?

A $X = OCH X_{3} > X = CH X_{3} > X = H > X = NO X_{2}$
B $X = OCH X_{3} > X = H > X = NO X_{2} > X = CH X_{3}$
C $X = NO X_{2} > X = H > X = CH X_{3} > X = OCH X_{3}$
D $X = CH X_{3} > X = OCH X_{3} > X = H > X = NO X_{2}$

Answer: A

Methoxy donates a lone pair (+M), which is the strongest stabilisation; methyl donates by +I and hyperconjugation. Hydrogen is the reference, and nitro destabilises the cation by -M and -I effects.

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Which is the correct order of stability of the para-substituted benzyl cations p-X−CX6​HX4​−CHX2​X+?

Answer: A

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Which is the correct order of stability of the para-substituted benzyl cations $p - X - C X_{6} H X_{4} - CH X_{2} X^{+}$ ?