Important Mesolithic human burials in the Ganga plain have been found at —

Sarai Nahar Rai and Mahadaha in Uttar Pradesh are important Mesolithic burial sites in the Ganga plain. Bhimbetka is known for rock shelters and paintings, while Lothal and Kalibangan are much later Harappan sites. Sarai Nahar Rai and Mahadaha fits that evidence because it matches the specific chronology, agency and function contained in the question. A comparison with the alternatives is useful: Bhimbetka, Lothal and Kalibangan are genuine historical terms or names, but each belongs to a different office, patron, text, region or sequence. Reading the question as a relationship among person, period, place and institutional purpose prevents that mistake. The compact memory link is therefore Sarai Nahar Rai and Mahadaha together with the factual context above, not the isolated option letter.