Which of the following is incorrect:

Options

A.
B.
C.
D.

Explanation

To determine which of the options is incorrect, we will analyze each option provided in the question step by step.

### Step 1: Analyze Option A
- **Statement**: Phenol with chloroform and potassium hydroxide undergoes a reaction known as the Drymer-Trimon reaction.
- **Explanation**: In this reaction, phenol reacts with chloroform in the presence of a strong base (potassium hydroxide) to form ortho and para-substituted products. The para product is generally the major product.
- **Conclusion**: This statement is correct.

### Step 2: Analyze Option B
- **Statement**: Aniline on treatment with chloroform and potassium hydroxide undergoes the carbylamine reaction, resulting in the formation of isocyanide.
- **Explanation**: The carbylamine reaction involves the reaction of primary amines (like aniline) with chloroform and a strong base (KOH) to produce isocyanides.
- **Conclusion**: This statement is also correct.

### Step 3: Analyze Option C
- **Statement**: Aniline with chloroform and KOH produces isocyanides.
- **Explanation**: This statement appears to be a repetition of the carbylamine reaction mentioned in Option B. However, if it implies that aniline does not produce isocyanides when treated with chloroform and KOH, then it is incorrect.
- **Conclusion**: This statement is incorrect.

### Step 4: Analyze Option D
- **Statement**: Phenol in the presence of carbon dioxide and a base gives salicylic acid.
- **Explanation**: This reaction is known as the Kolbe's electrolysis or the carboxylation of phenol, where phenol reacts with carbon dioxide in the presence of a base to form salicylic acid. However, if the statement implies that this reaction can occur without carbon dioxide, it is incorrect.
- **Conclusion**: This statement is also incorrect.

### Final Conclusion
The incorrect options are C and D.