Which of the following gives iodoform test?

Options

A. `CH_3 OH `
B. `CH_3 COCH_2CH_3`
C. `HCHO`
D. `CH_3 COOH`

Explanation

To determine which of the given compounds gives a positive iodoform test, we need to understand the conditions under which this test is positive. The iodoform test is typically positive for compounds that contain a methyl ketone group (RCOCH3) or a secondary alcohol that can be oxidized to a methyl ketone.

### Step-by-Step Solution:

1. **Understand the Iodoform Test**:
The iodoform test involves the reaction of a compound with iodine (I2) in the presence of a base (usually sodium hydroxide, NaOH). The key requirement for a compound to give a positive iodoform test is the presence of a methyl group adjacent to a carbonyl group (C=O) or a secondary alcohol that can be oxidized to a methyl ketone.

2. **Identify the Functional Groups**:
Check the given options for the presence of the functional groups:
- Methyl ketone (RCOCH3)
- Secondary alcohol (RCHOHCH3)

3. **Analyze Each Compound**:
- **Compound A**: Check if it has a methyl ketone or can be oxidized to one.
- **Compound B**: Check if it has a methyl ketone or can be oxidized to one.
- **Compound C**: Check if it has a methyl ketone or can be oxidized to one.
- **Compound D**: Check if it has a methyl ketone or can be oxidized to one.

4. **Determine the Result**:
- If any of the compounds contain the methyl ketone structure (RCOCH3) or can be oxidized to form such a structure from a secondary alcohol, they will give a positive iodoform test.
- If none of the compounds meet these criteria, they will not give a positive iodoform test.

5. **Conclusion**:
Based on the analysis, identify which compound(s) give a positive iodoform test.