The developments under charlemagne are sometimes referred to as the "carolingian renaissance." which of the following describes those changes? (1 point)

a) an increase in literacy, advancement of the arts, and improvements in the legal system.
b) a revival of polytheism, roman government, and roman construction.
c) an increase in the authority of the church, the state, and the serfs.
d) monarchs acquired the power to name bishops, dukes, and knights.