Step 1: Understanding the Question:
The question asks us to identify the specific 7-judge bench judgment of the Supreme Court that upheld the sub-classification of Scheduled Castes (SCs) and called for the identification of a "creamy layer" among SCs and STs.
Step 2: Key Concepts and Approach:
We need to analyze the recent judicial developments regarding reservations.
Previously, in E.V. Chinnaiah v. State of Andhra Pradesh (2005), a 5-judge bench had held that SCs form a homogeneous class and cannot be sub-classified.
We must identify the recent landmark decision that overruled this position.
Step 3: Detailed Explanation:
• State of Punjab v. Davinder Singh (2024): A 7-judge bench of the Supreme Court, led by the Chief Justice, delivered a historic 6:1 majority ruling.
• Sub-Classification Allowed: The Court held that SCs are not a homogeneous group and that states can sub-classify SCs and STs to provide targeted reservations for the most backward among them.
• Creamy Layer Imperative: The majority also observed that the "creamy layer" principle (which excludes affluent individuals from reservation benefits, originally applied only to OBCs) must be applied to SCs and STs as well to ensure substantive equality.
• Overruling Chinnaiah: This judgment directly overruled the E.V. Chinnaiah ruling.
Step 4: Final Answer:
The landmark case is State of Punjab v. Davinder Singh. Thus, Option A is correct.