The Sun provides energy by the process of nuclear_____.

Explanation

To answer the question "The Sun provides energy by the process of nuclear_____", we need to identify the correct term that describes how the Sun generates energy.

### Step-by-Step Solution:

1. **Understanding the Processes**:
- There are two main nuclear processes: nuclear fission and nuclear fusion.
- Nuclear fission is the splitting of a nucleus into smaller parts, while nuclear fusion is the combining of two light atomic nuclei to form a heavier nucleus.

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