Which part of the candle flame is coldest?

Explanation

**Step-by-Step Text Solution:**

1. **Understanding the Structure of a Candle Flame:**
- A candle flame consists of several parts: the outer zone, the inner zone, and the dark zone. Each part has different temperatures and characteristics.

2. **Identifying the Dark Zone:**
- The dark zone is the innermost part of the flame, which is not brightly lit. It appears darker compared to the outer parts of the flame.

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