The correct option is 2 only.
Explanation
The Constitution of India embodies a distinct model of secularism known as "principled distance." Unlike the Western model of strict separation between religion and the State, Indian secularism allows the State to intervene in religious affairs to uphold fundamental rights and ensure social reform, while maintaining equal respect for all religions.
Statement 1 is Incorrect:
When the Constitution was first framed and adopted in 1949, the Preamble defined India as a "Sovereign Democratic Republic." It did not contain the word "Secular." The terms "Socialist" and "Secular" were explicitly added to the Preamble later by the 42nd Constitutional Amendment Act, 1976.
Statement 2 is Correct:
To ensure the secular nature of the State, Article 28(1) of the Constitution mandates that "No religious instruction shall be provided in any educational institution wholly maintained out of State funds." This provision was included to distance the State from the propagation of any specific religion within public education.
Statement 3 is Incorrect:
The Constitution does not strictly prohibit the State from interfering in religious customs. Article 25(2)2 only explicitly empowers the State to make laws providing for social welfare and reform or for throwing open Hindu religious institutions of a public character to all classes and sections of Hindus. This allows the State to intervene to eradicate social evils (such as untouchability) even if they are rooted in religious traditions.
Key Takeaway:
Indian secularism is not a passive or negative concept of non-intervention; it is a positive concept that permits State intervention in religious matters specifically for the purpose of social reform and ensuring equality.