The correct answer is A. 41.
Arjun Munda was sworn in as the Chief Minister of Jharkhand on September 11, 2010. He was supported by a coalition of 41 MLAs from the Bharatiya Janata Party (BJP), the All Jharkhand Students Union (AJSU), and the Jharkhand Vikas Morcha (JVM). The Jharkhand Mukti Morcha (JMM) had the largest number of MLAs in the Assembly, with 37 seats. However, it was unable to form a government on its own. The Congress had 14 seats, and the Rashtriya Janata Dal (RJD) had 6 seats.
The BJP-AJSU-JVM coalition was able to form a government because it had the support of 41 MLAs, which was a majority of the 81 seats in the Assembly. The JMM, Congress, and RJD had a combined total of 57 seats, but they were unable to agree on a common candidate for Chief Minister. As a result, Arjun Munda was sworn in as the Chief Minister of Jharkhand on September 11, 2010.