the answer is indus:
footprints in volcanic ash. i believe is the answer sorry if wrong hope this
ok.you can know i am right because i have my history book right here.
answer: a. they conquered the maya.
explanation: the inca did do all of the following.
b. they had a highly organized military.
(proof) honestly, i could not find proof but i think this is the answer, i am sorry.
c. they mummified deceased royal family members.
(proof) " the ancient egyptians, the inca mummified their dead."
d. they built cities and fortresses on the highlands of the andes mountains.
(proof) "far to the south, along the spine of the andes mountains, rose another great " (btw this doesn't tell you it was from the inca, but it was the first sentence under the title - "the inca"