Concept:The date of adoption is when the Constituent Assembly formally approved the Constitution, which is different from the date it came into effect.
Explanation:The Constitution of India was adopted by the Constituent Assembly on November 26, 1949.
It came into effect later on January 26, 1950, which is celebrated as Republic Day.
Option A (August 15, 1947) is Independence Day, not adoption.
Option B (November 26, 1947) is incorrect; the adoption happened in 1949.
Option D (January 26, 1950) is the date of enforcement, not adoption.
Only option C matches the exact adoption date.
Answer:C. November 26, 1949