Final answer:
The Indian Constitution describes India as a Union of States and emphasizes the sharing of power between Union and State governments, which embodies the theory of Federalism. However, altering this power-sharing arrangement is not an easy task and cannot be altered independently by the Parliament. This makes options A I and II correct.
Step-by-step explanation:
The Indian Constitution describes the nation as a Union of States, which addresses option I. It aligns closely with the theory of Federalism, where there's a dual government system implying a clear division of powers between the Union and State governments. Thus, option II is also correct.
However, option III isn't accurate since the modification of the power-sharing agreement isn't an easy process as it requires a constitutional amendment, and this process needs a special majority of Parliament and ratification by states. The Parliament can't independently modify this arrangement, so option IV is also incorrect.
Therefore, the authentic statements relating to the theory of Federalism in the Indian Constitution are I and II, making the answer Option A: I & II.
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