___________ materials are made by modifying raw materials such as coal and petroleum through chemical reactions to obtain new materials.

Options

A. Man-made
B. Artificial
C. Natural
D. Both (a) and (b)

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a type of materials that are created by modifying raw materials such as coal and petroleum through chemical reactions.

2. **Identifying Raw Materials**: The raw materials mentioned are coal and petroleum. These are natural resources that can be transformed into various products.

3. **Chemical Reactions**: The process of modifying these raw materials involves chemical reactions that change their structure and properties to create new materials.

4. **Types of Materials Produced**: The materials produced from these processes are often used in various applications, including textiles, plastics, and other synthetic products.

5. **Naming the Materials**: The materials that are created through these processes are known as synthetic materials. Examples include nylon, acrylic, and bakelite.

6. **Final Answer**: Therefore, the blank in the question can be filled with the term "Synthetic" or "Manmade" materials.

**Complete Answer**: Synthetic materials are made by modifying raw materials such as coal and petroleum through chemical reactions to obtain new materials.

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