Answer: b. Built a huge ancient empire
Explanation: Pachacuti was the ninth Sapa Inca of the Kingdom of Cusco that triggered the transformation of that kingdom into the Inca Empire.
During his reign, an era of conquest began that, in three generations, expanded the Inca domain from the Cusco Valley to much of western South America, so, while Pachacuti was in power, Cusco went from a simple village to be an empire that ended up surpassing Chimú.