Pick the wrong answer in the context with rainbow.

Options

A. Rainbow is combined effect of dispersion, refraction and reflection of sunlight
B. When the light rays undergo two internal reflections in a water drop, a secondary rainbow is formed
C. The order of colours is reversed in the secondary rainbow.
D. An observer can see a rainbow when his front is towards the sun.

Explanation

To solve the question of identifying the wrong statement in the context of a rainbow, we will analyze each statement provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding the Formation of a Rainbow**:
- A rainbow is formed due to the combination of three optical phenomena: dispersion, refraction, and reflection of sunlight in water droplets.
- When sunlight enters a water droplet, it bends (refraction), separates into its constituent colors (dispersion), and reflects off the inside surface of the droplet.

2. **Analyzing the Statements**:
- **Statement 1**: "Rainbow is a combined effect of dispersion, reflection, and refraction of sunlight."
- This statement is **correct**. The formation of a rainbow indeed involves all three processes.

- **Statement 2**: "When the light rays undergo two internal reflections in a water droplet, a secondary rainbow is formed. The order of the colors is reversed in the secondary rainbow."
- This statement is also **correct**. The secondary rainbow forms when light reflects twice inside the droplet, leading to a reversal of the color order compared to the primary rainbow.

- **Statement 3**: "An observer can see a rainbow when his front is towards the sun."
- This statement is **incorrect**. For an observer to see a rainbow, the sun must be behind them, with the water droplets in front of them. The light must enter the droplets from behind the observer.

3. **Conclusion**:
- The wrong statement in the context of a rainbow is **Statement 3**: "An observer can see a rainbow when his front is towards the sun."

### Final Answer:
The wrong answer in the context of a rainbow is: **An observer can see a rainbow when his front is towards the sun.**

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