What is the legal nature of the Preamble of the Constitution?

The Preamble to the Constitution of India is :

Which of the following words is NOT mentioned in the Preamble of the Constitution of India?

Which among the following is not mentioned in the Preamble to the Constitution of India?

In which case did the Supreme Court first declare that the Preamble is not a part of the Constitution?

Who called the Preamble as Political Horoscope of Indian Constitution?