Phenol is treated with chloroform (CHCl₃) and aqueous NaOH at $340$ K, followed by acidification. What is the major product?

**Reimer–Tiemann reaction.** Phenol + CHCl₃ + NaOH (with heat) → ortho-hydroxybenzaldehyde, i.e. **salicylaldehyde** as the major product. **Mechanism in one breath**: NaOH dehydrohalogenates CHCl₃ to generate the electrophilic carbene `:CCl₂` (dichlorocarbene). The phenoxide (formed by NaOH deprotonating phenol) attacks `:CCl₂` *ortho* to the –OH; subsequent hydrolysis of the dichloromethyl group yields the –CHO. **Why the distractors are tempting.** Picric acid (C) is the *nitration* product of phenol with concentrated HNO₃. Benzoic acid (A) requires oxidation, not Reimer–Tiemann. Anisole (D) is the methylation product.