Constitution of India was passed and adopted on:
The correct answer is option 'C' - 26 November 1949.

Explanation:
The Constitution of India is the supreme law of the country, which lays down the framework that defines the political principles, establishes the structure, procedures, powers, and duties of the government institutions and sets out the fundamental rights, directive principles, and responsibilities of citizens. It was drafted by a constituent assembly and was adopted on 26 November 1949.

Process of Constitution-making:
1. Constituent Assembly: The process of constitution-making in India began with the formation of the Constituent Assembly on 9 December 1946, which was tasked with drafting the Constitution for independent India.
2. Drafting Committee: The Constituent Assembly appointed a drafting committee on 29 August 1947, chaired by Dr. B.R. Ambedkar. The committee was responsible for framing the Constitution of India.
3. Deliberations and Amendments: The drafting committee and the constituent assembly held several deliberations and discussions over a period of almost three years. The Constitution was debated, amended, and refined to reflect the aspirations and principles of the people of India.
4. Adoption: After the finalization of the draft, the Constitution was adopted by the Constituent Assembly on 26 November 1949. It was signed and accepted by the members of the assembly, making it the official Constitution of India.
5. Effective Date: The Constitution of India came into effect on 26 January 1950, marking the transition of India from a dominion to a republic. This day is celebrated as Republic Day in India.

Significance:
The adoption of the Constitution of India marked a significant milestone in the country's history. It established India as a sovereign, socialist, secular, and democratic republic, ensuring justice, liberty, equality, and fraternity for all its citizens. The Constitution provided a comprehensive framework for the functioning of the government, protection of fundamental rights, and promotion of social justice.

Overall, the Constitution of India was passed and adopted on 26 November 1949, and it came into effect on 26 January 1950, heralding the birth of the Republic of India.