Under Section 25-F of the Industrial Disputes Act, 1947, which of the following conditions must be fulfilled before retrenching a workman who has been in continuous service for not less than one year?

Section 25-F prescribes three cumulative conditions for retrenchment of a workman in continuous service for not less than one year: (a) the workman must be given one month's notice in writing indicating the reasons for retrenchment, or wages in lieu of such notice; (b) the workman must be paid retrenchment compensation equivalent to 15 days' average pay for every completed year of continuous service or any part thereof in excess of six months; and (c) notice in the prescribed manner must be served on the appropriate Government. Non-compliance with any of these conditions renders the retrenchment invalid. The Supreme Court in Workmen v. Hindustan Steel Ltd. (1984) affirmed that these are mandatory prerequisites and cannot be dispensed with.