Which statement correctly describes the origins or major features of the caste system

The only true option from the list would be that "In time a fifth group was added to the caste system--the untouchables," since this was a later development and not an initial part of the system.

Explanation:

lincoln presided over the union victory in the american civil war, which dominated his presidency. a former whig, lincoln ran on a political platform opposed to the expansion of slavery in the territories. his election served as the immediate impetus for the outbreak of the american civil war.