Question

name sections of society which have been exploited for centuries

Answer 1

Dalits (mainly), SCs, STs and Once are the sections that have been exploited for centuries.

Answer 2

The sections that have been mainly exploited for centuries are Dalits, SCs (Schedule Caste), STs (Schedule tribe).

The present caste system is slightly modified. Mainly Kshatriyas and Shudras are divided into further classes.

All these classes are now called as castes. Indians, through ages, have married people only within their caste and hence their whole extended family and relatives belong to the same caste.