Punishment prescribed under section 18 of the Hindu Marriage Act for child marriage is-

Incorrect. Section 18(a) of the Hindu Marriage Act, 1955 does not restrict the sentence to imprisonment alone; the court may impose imprisonment, or fine, or both.

Incorrect. Section 18(a) of the Hindu Marriage Act, 1955 does not limit the punishment to fine alone; it provides for rigorous imprisonment up to two years, or fine up to one lakh rupees, or both.

Correct. Under Section 18(a) of the Hindu Marriage Act, 1955 (as amended by the Prohibition of Child Marriage Act, 2006), a person who procures a marriage of himself or herself in contravention of Section 5(iii) (minimum age for marriage) is punishable with rigorous imprisonment which may extend to two years, or with fine which may extend to one lakh rupees, or with both.

Incorrect. Under Section 18(a) of the Hindu Marriage Act, 1955, the phrase is disjunctive/alternative ('imprisonment ... or with fine ... or with both'), not mandatory conjunctive imprisonment and fine in every case.