When all the colours of white light are reflected back from an object, then object with appear:

Options

A. blue
B. green
C. black
D. white

Explanation

To solve the question, "When all the colors of white light are reflected back from an object, then the object will appear:", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding White Light**: White light is composed of a mixture of all colors in the visible spectrum. This includes red, orange, yellow, green, blue, indigo, and violet.

2. **Reflection of Light**: When light hits an object, some wavelengths (colors) of light may be absorbed by the object, while others are reflected. The color that we perceive an object to be is determined by the wavelengths of light that are reflected back to our eyes.

3. **Condition of Reflection**: The question states that "all the colors of white light are reflected back from an object." This means that the object does not absorb any color; it reflects every color of the spectrum.

4. **Resulting Color Perception**: When an object reflects all colors of white light, it appears white to our eyes. This is because our eyes combine all the reflected colors, and the combination of all colors results in the perception of white.

5. **Conclusion**: Therefore, when all the colors of white light are reflected back from an object, the object will appear white.

### Final Answer:
The object will appear **white**.

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