To understand who arrived at the conclusion that social inequalities in rural society have transformed from "cumulative inequalities to dispersed inequalities," we need to delve into the work and contributions of the sociologists listed in the options.

The correct answer to this question is Andre Beteille. To clarify:

1. M.N. Srinivas: Known for his work on caste and social structure in India, Srinivas introduced the concept of 'Sanskritization', which discusses the process of caste mobility in Indian society. However, he did not focus explicitly on the transformation from cumulative to dispersed inequalities in rural societies.
2. F.G. Bailey: Bailey's work primarily focused on political systems and social stratification, with studies on Orissa. His analyses often discuss power dynamics but do not emphasize the shift from cumulative to dispersed inequalities.
3. Andre Beteille: Beteille's extensive research on stratification in Indian society, especially his study on the village of Sripuram, suggests the transformation in understanding social inequalities. His analysis highlights how different sources of power (economic, social, political) are not concentrated but spread among different groups, thus forming 'dispersed inequalities'.
4. Yogendra Singh: While Singh has significant contributions to sociology, including modernization and social change, he does not specifically focus on the shift from cumulative to dispersed inequalities.

Thus, it is Andre Beteille who concluded the shift from "cumulative inequalities" where power was concentrated among few, to "dispersed inequalities" where power is more spread out, in rural society. This understanding helps us grasp the nature of social stratification and transformation in rural India.