The correct option is United States.
Explanation
The Indian Constitution drew upon various sources for its structural and philosophical foundations. The concept of Fundamental Rights, enshrined in Part III of the Constitution, was primarily inspired by the Bill of Rights of the United States Constitution.
Analysis of Sources:
- United States: The Bill of Rights (the first ten amendments to the US Constitution) guarantees essential rights and liberties to citizens. This served as the model for India's Fundamental Rights (Articles 12-35), which are justiciable in nature.
- France: The ideals of Liberty, Equality, and Fraternity appearing in the Preamble were borrowed from the French Constitution.
- United Kingdom: Features such as the Parliamentary form of government, Rule of Law, Single Citizenship, and the institution of the Speaker were adopted from the British Constitution.
- Ireland: The Directive Principles of State Policy (DPSP) and the method of election of the President were borrowed from the Irish Constitution.
Key Takeaway: Part III of the Indian Constitution, often termed the "Magna Carta of India," derives its inspiration regarding Fundamental Rights from the USA (Bill of Rights).