Step 1: Understanding the Question:
The question asks us to identify the author and the specific subject matter of the famous legal quote: "These rules can operate only in areas not covered by any law validly made and they do not supplant the law of the land but supplement it."
Step 2: Key Legal Principles and Approach:
This quote addresses the relationship between codified statutory law and the uncodified principles of natural justice.
We must recall the landmark Supreme Court of India judgment that integrated natural justice into the administrative framework.
Step 3: Detailed Explanation:
• The Author and the Case: This classic statement was made by Justice K.S. Hegde in the pathbreaking case of A.K. Kraipak v. Union of India (AIR 1970 SC 150).
• Hence, statement (A) is correct.
• The Subject Matter ("These Rules"): In this quote, "these rules" refers explicitly to the principles of natural justice.
• Justice Hegde explained that the principles of natural justice are meant to prevent the miscarriage of justice.
• They do not override or "supplant" express statutory provisions; rather, they "supplement" the written law of the land.
• If a statute is silent on a procedure, the court will read the requirements of fair play and natural justice into the gaps of the statute.
• Hence, statement (C) is correct.
• Evaluating Statement (B): Statement (B) claims that "rules" refers to executive rules.
• This is incorrect because the court was specifically discussing the principles of natural justice, not administrative rules or regulations.
• Since both (A) and (C) are correct, Option (D) ("Only (a) and (c)") is the correct choice.
Step 4: Final Answer:
The quote was delivered by Justice Hegde in the *A.K. Kraipak* case regarding the supplementary nature of the principles of natural justice, making Option (D) the correct answer.