Pick out the correct statements from the following
I. Electron emission during `Brta`-decay is always accompanied by neutrons.
II. Nuclear force is charge independent.
III. Fusion is the chief source of stellar energy.

Options

A. Both I and II are correct
B. Both I and III are correct
C. Only I is correct
D. Both II and III are correct

Explanation

To solve the question, we need to evaluate each of the given statements regarding their correctness.

### Step 1: Evaluate Statement I
**Statement I:** "Electron emission during beta decay is always accompanied by neutrons."

- In beta decay, specifically beta minus decay, a neutron in the nucleus decays into a proton, an electron (beta particle), and an antineutrino.
- Therefore, the emission of an electron is accompanied by a proton, not a neutron.
- **Conclusion:** This statement is **false**.

### Step 2: Evaluate Statement II
**Statement II:** "Nuclear force is charge independent."

- The nuclear force acts between nucleons (protons and neutrons) and is indeed charge independent.
- This means that the strength of the nuclear force does not depend on the charge of the particles involved. It acts the same between proton-proton, neutron-neutron, and proton-neutron pairs.
- **Conclusion:** This statement is **true**.

### Step 3: Evaluate Statement III
**Statement III:** "Fusion is the chief source of stellar energy."

- In stars, including our Sun, the primary process for energy production is nuclear fusion.
- In this process, hydrogen nuclei fuse to form helium, releasing a significant amount of energy in the form of radiation.
- **Conclusion:** This statement is **true**.

### Final Conclusion
From the evaluations:
- Statement I is false.
- Statement II is true.
- Statement III is true.

Thus, the correct statements are II and III. Therefore, the answer is that statements II and III are correct.

### Summary of Correct Statements
- **Correct Statements:** II and III.