The correct option is C 26 January 1950
The Constitution of India was adopted by the Constituent Assembly on 26 November 1949 and came into effect on 26 January 1950. The Constituent Assembly was the main body responsible for drafting the constitution of India that would lay the basis of governance. The Constitution lays down the foundations of the government under which the people of the country are to be governed. The Indian constitution has 25 parts, 12 schedules, and 448 articles, thus, making it the longest constitution ever drafted in the history of mankind.