The President of India in their role as head of Legislature has the authority to summon and to dissolve either house of Parliament. to summon and discontinue either house of Parliament. A bill passed by the Parliament turns into law only after the President gives his nod to it. While the President has the authority to return a bill for reconsideration to the Parliament, they have to sign it if the Parliament still chooses to pass the bill (with or without any amendment).
In a parliamentary system, the Council of Ministers depends on the support of the majority in the legislature. They can be removed at any point and a new Council can be brought in to replace them. A situation of this nature requires a Head of the State to step in as they symbolically represent the country and are vested with the authority to appoint the Prime Minister. This is the key role of the President of India. Additionally, if no majority party is established then it is up to the President to select and appoint the Prime Minister.
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