Concept:Article 78 of the Indian Constitution specifically obligates the Prime Minister to communicate all decisions of the Council of Ministers to the President.
Explanation:The Prime Minister is the head of the Council of Ministers and the chief link between the Cabinet and the President.
Under Article 78, the Prime Minister must: (a) communicate all decisions of the Council of Ministers to the President, (b) furnish any information the President may request, and (c) submit any matter for the Council's consideration if the President so requires.
This ensures the President stays informed about executive actions, even though the President is the nominal head.
Article 74 deals with the Council of Ministers aiding and advising the President.
Article 75 covers the appointment and tenure of ministers and collective responsibility to the Lok Sabha.
Article 81 specifies the composition of the Lok Sabha.
Thus, only Article 78 mandates the Prime Minister to report Cabinet decisions to the President.
Answer:Article 78