The process used to harness nuclear energy these days is

Options

A. Nuclear fission
B. Nuclear fusion
C. Alpha decay
D. All of these.

Explanation

**Step-by-Step Solution:**

1. **Understanding Nuclear Energy**: Nuclear energy is derived from the nucleus of atoms. It can be harnessed through various processes, primarily nuclear fission and nuclear fusion.

2. **Identifying the Current Process**: The question asks about the current process used to harness nuclear energy. The video mentions nuclear fusion as the primary process being utilized today.

3. **Defining Nuclear Fusion**: Nuclear fusion is a process where two light atomic nuclei combine to form a heavier nucleus. This process releases a significant amount of energy.

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