Study the diagram and answer the questions that follow :
Name the hard substance covering the crown of the tooth.

Explanation

**Step-by-Step Solution:**

1. **Identify the Diagram**: Begin by closely examining the diagram provided in the question. Look for the part of the tooth that is referred to as the "crown."

2. **Understand the Structure of the Tooth**: The tooth consists of several parts, including the crown, root, and neck. The crown is the visible part of the tooth above the gum line.

3. **Recognize the Hard Substance**: The crown of the tooth is covered by a hard substance. This substance is crucial for protecting the tooth from wear and tear during chewing.

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