In Liebermann’s nitroso reaction, change in colour of phenol occurs as:A. Brown or red-greenish red-deep blueB. Red-deep blue-greenC. Red-green-whiteD. White-red-green

In Liebermann’s nitroso reaction, phenols react with nitrous acid (\( HNO_2 \)) to form nitroso derivatives. This reaction is significant because it involves a color change that can be observed visually.

### Color Change in Liebermann's Nitroso Reaction:
1. **Starting with Phenol:** When phenol is treated with nitrous acid, the reaction leads to the formation of a nitroso compound.
2. **Observing Color Changes:**
- The initial color of the solution is typically brown or reddish.
- As the reaction proceeds, it can change to greenish-red or deep blue, depending on the specific phenolic compound being used and the conditions of the reaction.

### Answer Breakdown:
- **Option A: Brown or red-greenish red-deep blue** — This option accurately describes the expected color changes in the reaction.
- **Option B: Red-deep blue-green** — This is a less accurate sequence.
- **Option C: Red-green-white** — This does not reflect the typical color changes in the reaction.
- **Option D: White-red-green** — This also does not accurately describe the color transitions.

### Conclusion:
The correct answer is **A: Brown or red-greenish red-deep blue**. This option best represents the series of color changes that occur during the Liebermann's nitroso reaction involving phenol.