Arrange the following compounds in increasing order of their acidic character.

(A) m-nitrophenol
(B) p-nitrophenol
(C) Phenol
(D) p-methoxyphenol

Choose the correct answer from the options given below:

(D), (C), (A), (B)

The correct answer is Option (4) → (D), (C), (A), (B)

Acidity of phenols depends on the electron-withdrawing or electron-donating groups attached to the ring:

• EWGs (–NO₂) increase acidity by stabilizing the phenoxide ion.
• EDGs (–OCH₃) decrease acidity by destabilizing the phenoxide ion.
• Position of substituent matters: ortho > para > meta for –NO₂ due to resonance and inductive effects.

Given compounds:

1. D: p-methoxyphenol → EDG → least acidic
2. C: Phenol → neutral → more acidic than D
3. A: m-nitrophenol → meta NO₂ → more acidic than C
4. B: p-nitrophenol → para NO₂ → most acidic (resonance stabilization)

Increasing order of acidity:

$\text{D} < \text{C} < \text{A} < \text{B}$