The process of combining of two lighter nuclei to form a large nucleus accompanied by release of huge amount of energy is called nuclear___

Explanation

To solve the question, we need to identify the correct term that describes the process of combining two lighter nuclei to form a larger nucleus, which is accompanied by the release of a significant amount of energy.

### Step-by-Step Solution:

1. **Understanding the Process**: The question describes a process where two lighter atomic nuclei come together to form a heavier nucleus. This process is known for releasing a large amount of energy.

2. **Identifying Key Terms**: The two terms we are considering are "nuclear fusion" and "nuclear fission".
- **Nuclear Fusion**: This is the process of combining two lighter nuclei to form a heavier nucleus, releasing energy in the process.
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