Let's analyze the statements based on the Industrial Disputes Act, 1947.
Statements (A), (B), and (C) are all true and reflect the provisions of Sections 22, 23, and 25 of the Act, which place restrictions on strikes and lock-outs.
Statement (D) is not true.
Section 22(1) of the Act prohibits a person in a public utility service from going on strike without giving notice, but it also provides a cooling-off period.
It states that no person shall go on strike within fourteen days of giving such notice.
This 14-day period is meant to allow for conciliation and negotiation.
Striking within seven days would violate this mandatory 14-day cooling-off period.