Which document was signed by most of the rulers of the states before 15th August 1947, that their states agreed to become a part of the Union of India?

Instrument of Accession

The correct answer is option (3) - Instrument of Accession

The Instrument of Accession: It was a unilateral agreement signed by the rulers of princely states to join India or Pakistan after the end of British rule in 1947. By signing the Instrument of Accession, the princely state surrendered control over matters related to defence, foreign affairs, communication etc. to the Dominion of India or Pakistan, depending on their choice and agreed to become a part of that country.


Government’s Approach towards Partition & Princely states:
The interim government firmly opposed the division of India into small principalities.
The Muslim League differed from the Indian National Congress, advocating for the states' freedom to choose their own course.
The task of bringing the princely states together was complex and required skilful persuasion, considering a large number of states and different administrative structures.
Sardar Patel, India's Deputy Prime Minister and Home Minister, played a crucial role in diplomatically negotiating with the rulers of princely states and integrating them into the Indian Union.
He was assisted by V.P. Menon, a senior civil servant to carry out this task smoothly and successfully.
Three considerations guided the government's approach:  
The desire of the people to join the Indian Union.
Flexibility in granting autonomy to specific regions.
Importance of consolidating the nation's territorial boundaries.
Before August 15, 1947, peaceful negotiations resulted in most states within India's new boundaries joining the Indian Union through the signing of the "Instrument of Accession".