Complete the following sentences by choosing the correct term from the worá bank.
nuclear fission, nuclear fusion, nuclear chain reaction
During __________ small nuclei combine.

Explanation

To complete the sentence, we need to choose the correct term from the word bank provided: "nuclear fission," "nuclear fusion," or "nuclear chain reaction."

1. **Understanding the Terms**:
- **Nuclear Fission**: This is a process where a large nucleus splits into smaller nuclei, releasing energy in the process.
- **Nuclear Fusion**: This is a process where small nuclei combine to form a larger nucleus, also releasing energy.
- **Nuclear Chain Reaction**: This refers to a series of reactions where the products of one reaction initiate further reactions.

2. **Analyzing the Sentence**:
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