प्रतिपादन (A) : केशवानंद भारती वि. केरळ राज्य या प्रकरणात सर्वोच्च न्यायालयाने असे जाहीर केले की घटनेच्या मूलभूत संरचनेत दुरुस्ती करता येणार नाही.
कारण (R) : सर्वोच्च न्यायालयाने, संसदीय सार्वभौमत्व आणि न्यायालयीन पुनर्विलोकन यामधे संतुलन आणले.

The correct answer is Option A (Both A and R are true and R is the correct explanation of A.).

Key Points:
• The Landmark Verdict: On 24th April 1973, a historic 13-judge bench of the Supreme Court delivered the ruling in Kesavananda Bharati v. State of Kerala. By a 7:6 majority, the Court propounded the Doctrine of Basic Structure.
• Assertion Validation: The Court ruled that under Article 368, Parliament possesses vast powers to amend any part of the Constitution, including Fundamental Rights, but it cannot alter or destroy the Basic Structure or essential features of the Constitution.
• Harmonious Balance: Prior to this, *Golaknath (1967)* had frozen Parliament's amending power regarding Fundamental Rights, and the *24th Amendment (1971)* asserted unchecked constituent sovereignty. The Supreme Court harmonized British-style Parliamentary Sovereignty with American-style Judicial Supremacy, recognizing constituent amending power while retaining judicial review to safeguard core democratic foundations.
• Key Result: Reason (R) correctly explains Assertion (A).
• Key Takeaway: Kesavananda Bharati (1973) established that Parliament cannot alter the Basic Structure, balancing Parliamentary power with Judicial Review.