Explanation
The Preamble to the Constitution of India is an introductory statement that sets forth the objectives and purposes of the Constitution. It was adopted on 26th November 1949, and was amended only once by the 42nd Amendment Act of 1976.
The 42nd Amendment Act added three new words to the Preamble: Socialist, Secular, and Integrity. Prior to this amendment, the Preamble did not contain these words.
Therefore, the correct answer is option D: None of these.
The terms "Socialist", "Secular", and "Integrity" were introduced to the Preamble by the 42nd Amendment Act.
