Explanation:

- Article 42 of the Indian Constitution focuses on making work conditions just and humane and provides for maternity relief.

- Option 1: Social reform

This fits best, as improving work conditions and maternity relief are social measures aimed at benefiting workers and families.

- Option 2: Economic reform

While there can be some economic impact, the aim is not directly economic policy change but ensuring welfare.

- Option 3: Legal reforms

Legal provisions might be made, but the core intention is social justice, not merely changing laws for their own sake.

- Option 4: Police reform

This is unrelated, as Article 42 is about workers’ welfare, not police systems or reform.

Correct Answer: Social reform.