Who among the following became the Chief Minister of Maharashtra in December…

Concept: Under Article 164 of the Constitution, the Governor of a State appoints as Chief Minister the person who commands the confidence of a majority in the Legislative Assembly. After a general election to the Assembly, that person is whoever the winning party or coalition elects as its legislature-party leader, so the office follows the post-poll numbers and the alliance's own choice rather than seniority or incumbency.

Application: Polling for all 288 seats of the Maharashtra Legislative Assembly was held on 20 November 2024 and the results were declared on 23 November 2024. The Mahayuti alliance won about 230 seats, of which the BJP alone took 132, the single largest tally in the House. On 4 December 2024 the BJP legislature party elected Devendra Fadnavis as its leader and the alliance backed him for the top post. He took oath as Chief Minister of Maharashtra on 5 December 2024 at Azad Maidan in Mumbai, with Eknath Shinde and Ajit Pawar sworn in as Deputy Chief Ministers. This was Fadnavis's third term as Chief Minister, after 2014-2019 and a brief term in November 2019.

Cross-check: where each of the four leaders stood around the November-December 2024 change of government.

Hence the leader who became Chief Minister of Maharashtra in December 2024, after the November 2024 Assembly elections, was Devendra Fadnavis.