The answer is: B
Explanation
The correct option is B: 26th January, 1950.
This is the date when the Constitution of India came into effect, declaring India as a Sovereign, Socialist, Secular, and Democratic Republic.
The date was chosen to commemorate the anniversary of the Poorna Swaraj declaration of 1930, when Indian freedom fighters demanded complete independence from British rule. The Constitution of India was adopted by the Constituent Assembly on 26th November, 1949, after nearly three years of deliberation and drafting.
It is the longest written constitution of any sovereign country in the world, containing 395 articles and 12 schedules. It is also considered as a living document, as it has been amended 103 times till date.