Which phrase best completes the partial outline below?
I. Achievements of the Incas
A. _____________________________
B. Kept records using quipus
C. Built stone structures without using mortar

a. Cast bronze statues c. invented a foot stirrup
b. created a system of terraced
farming
a. Cast bronze statue b. created a system of terraced farming
c. invented a foot stirrup d. developed chariots