Select all choices that apply. mark if an event led to the decline of the inca empire. a. pizarro sailed down the west coast of south america to peru. b. disease and civil war ravaged the inca empire. c. the spanish sent messages of peace and friendship to the inca. d. the inca learned from the aztecs’ mistakes and killed every spaniard they encountered. e. pizarro took atahualpa hostage and then had him executed.