In which of the following reactions, alcohol is formed as product gives positive iodoform test?

Options

A. `CH_(3)-overset(O)overset(||)C-CH_(3)overset("Ph - MgBr")underset("H OH/H"^(+))rarr`
B. `CH_(3)-CH_(2)-CH=Ooverset("(I) "CH_(3)MgBr" (excess)
(II)H_(2)O/H^(+))rarr`
C. `H-overset(O)overset(||)C-OEt overset(""(i) PhMgBr (excess)")underset("(ii) "HOH//H^(+))rarr`
D. `CH_(3)-overset(O)overset(||)C-OE t overset("(i) PhMgBr (excess)")underset("(ii) "HOH//H^(+))rarr`

Answer

To determine which reaction produces an alcohol that gives a positive iodoform test, we need to analyze each option carefully. The iodoform test is positive for methyl ketones or secondary alcohols that can be oxidized to methyl ketones.

### Step-by-Step Solution:

1. **Understanding the Iodoform Test**:
- The iodoform test is used to identify the presence of methyl ketones (RCOCH3) or secondary alcohols that can be oxidized to methyl ketones. A positive test results in the formation of a yellow precipitate of iodoform (CHI3).

2. **Analyzing Each Option**:
- **Option A**: The reaction involves a tertiary alcohol. Tertiary alcohols do not give a positive iodoform test because they cannot be oxidized to a methyl ketone.
- **Conclusion for Option A**: **Does not give a positive iodoform test**.

- **Option B**: The reaction produces a secondary alcohol (RCH(OH)R'). Secondary alcohols can be oxidized to methyl ketones.
- **Conclusion for Option B**: **Gives a positive iodoform test**.

- **Option C**: This option also produces a secondary alcohol. Similar to option B, this secondary alcohol can be oxidized to a methyl ketone.
- **Conclusion for Option C**: **Gives a positive iodoform test**.

- **Option D**: The product is a tertiary alcohol. As established, tertiary alcohols do not give a positive iodoform test.
- **Conclusion for Option D**: **Does not give a positive iodoform test**.

3. **Final Evaluation**:
- From the analysis, **Option B and Option C** yield secondary alcohols that can be oxidized to methyl ketones, resulting in a positive iodoform test.

### Final Answer:
**Options B and C give a positive iodoform test.**