In the zone of _____, the wax vapours coming out of the candle burn completely due to sufficient supply.

Options

A. Incomplete combustion
B. Luminous combustion
C. complete combustion
D. No combustion

Answer

To answer the question, we need to identify the correct term that describes the zone where the wax vapors from a candle burn completely due to a sufficient supply of oxygen.

### Step-by-Step Solution:

1. **Understanding Candle Combustion**: A candle burns by melting the wax, which then vaporizes. The wax vapors mix with oxygen in the air and burn to produce heat and light.

2. **Identifying the Zones of a Flame**: A candle flame has different zones, each with distinct characteristics. The main zones are:
- The outer zone (or the zone of complete combustion)
- The inner zone (or the zone of incomplete combustion)
- The zone of luminous flame (where the flame is yellow and emits light)

3. **Focusing on the Zone of Complete Combustion**: In the context of a candle flame, the zone where the wax vapors burn completely is known as the zone of complete combustion. This zone has a sufficient supply of oxygen, allowing for the complete burning of the wax vapors.

4. **Final Answer**: Therefore, the correct term to fill in the blank is "complete combustion".

The complete sentence would be: "In the zone of complete combustion, the wax vapours coming out of the candle burn completely due to sufficient supply."