Step 1: Legal provisions.
According to Section 52 of the Companies Act, 2013, Securities Premium Account can be used for:
- Issuing fully paid bonus shares.
- Writing off preliminary expenses, commission, discount on issue.
- Paying premium on redemption of preference shares or debentures.
- Buy-back of own shares.
Step 2: Analyze options.
(A) To issue partly paid bonus shares → Incorrect (law permits only fully paid bonus shares).
(B) Buy back of own shares → Correct.
(C) To write-off expenses, commission or discount → Correct.
(D) To pay premium on redemption → Correct.
Step 3: Conclusion.
Therefore, the correct set is (B), (C) and (D).
Final Answer: \[ \boxed{(B), (C) \text{ and } (D) \text{ only}} \]