Step 1: Directive Principles.
Article 40, under the Directive Principles of State Policy, directs the State to organize village panchayats and endow them with necessary powers for self-government.
Step 2: Options analysis.
(A) Article 31: Related to property rights (now repealed).
(B) Article 35: Deals with Parliament’s power to make laws.
(C) Article 40: Correct — explicitly mentions local self-government (Panchayati Raj).
(D) Article 42: Relates to maternity relief.
Step 3: Conclusion.
Thus, the correct answer is Article 40.