What Was the Benefit to the Spanish Crown of an Encomienda

What was the benefit to the Spanish crown of an encomienda?

A) The crown could use the encomienda to directly oversee missionary work among the Indians.
B) The crown could use the encomienda to export Iberian prisoners to work mines in the Americas.
C) The crown received special taxes on the extraction of precious metals from the encomenderos.
D) The crown could use the encomenderos as forced labor on sugar plantations.