The zone that produces yellow light in the candle flame is

Options

A. non-luminous zone
B. luminous zone
C. invisible zone
D. all zones give light.

Explanation

**Step-by-Step Solution:**

1. **Understanding Candle Flame Zones**: A candle flame consists of different zones, each with distinct characteristics. The main zones are the luminous zone, non-luminous zone, and dark zone.

2. **Identifying the Luminous Zone**: The luminous zone is the middle part of the candle flame. This zone is known for producing yellow light.

3. **Combustion Type**: In the luminous zone, combustion is incomplete due to a limited supply of oxygen. This incomplete combustion results in the production of soot and the characteristic yellow light.

4. **Analyzing Other Zones**:
- The non-luminous zone, which is the outermost zone, burns with a blue flame due to complete combustion, where there is an excess of oxygen.
- The dark zone, also known as the invisible zone, does not produce light and appears black.

5. **Conclusion**: Based on the characteristics of the zones, the zone that produces yellow light in a candle flame is the luminous zone.

**Final Answer**: The zone that produces yellow light in the candle flame is the **luminous zone**.

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