What do the encomienda, mita, and debt peonage have in common?

AThey were all social systems of discriminating between various racial combinations found in Iberian colonies in South America

BThey were all economic systems of providing labor for Spanish migrants seeking to make a living in the Iberian colonies of South America

CThey were all part of the Spanish system of governing her New World colonies and were designed to enforce royal control of distant lands

DThey were all part of the process of conversion among the indigenous peoples of South America to Roman Catholicism