Which, amongst the following, is the latest language to be included in the Eighth Schedule of the Constitution of India?

Maithili was the latest among the given options to be added to the Eighth Schedule of the Constitution of India. It was added through the 92nd Constitutional Amendment Act, 2003, along with Bodo, Dogri, and Santhali, bringing the total number of scheduled languages to 22. Nepali, Konkani, and Manipuri were added earlier through the 71st Amendment Act of 1992. Hence, Maithili is the most recent inclusion among the options provided.