Answer to Question 1
a. subsistence
Answer to Question 2
India's cast system is based on religion rather than race. The system is nearly three thousand years old.The four main castes are (top to bottom):Brahman (priests and teachers); Kshatriya (rulers and soldiers); Vaishya (merchants and traders); Shudra (peasants and laborers); and Dalit (outcasts). Although the system was officially abolished in 1949, it persists.