_________ burn(s) with a yellow flame with a smell of burning hair.

Options

A. Silk and wool
B. Cotton and rayon
C. Nylon and polyester
D. Acrylic

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which material burns with a yellow flame and produces a smell similar to that of burning hair.

2. **Identifying the Options**: The options provided are:
- Acrylate
- Nylon
- Polyester
- Silk
- Wool
- Cotton

3. **Classifying the Materials**:
- Acrylate, Nylon, and Polyester are synthetic fibers.
- Silk and Wool are natural fibers.
- Cotton is also a natural fiber.

4. **Analyzing the Burning Characteristics**:
- Natural fibers, such as silk and wool, tend to burn with a yellow flame and emit a smell similar to burning hair. This is because they are composed of proteins, similar to human hair.
- Synthetic fibers, on the other hand, do not typically burn in this manner.

5. **Choosing the Correct Answer**: Since the question specifies the burning characteristics and the smell, the correct answer would be either silk or wool. However, since the question format suggests a single answer, we can conclude that the answer is:
- **Silk or Wool** (depending on the options provided).

6. **Final Answer**: The answer to the question is **Silk or Wool**.

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