"to achieve the degree of development shown, the aztecs first had to
(1)invent wheeled vehicles to move construction materials
(2)use domesticated animals to assist in agriculture
(3)establish an organized government and a specialized work force
(4)adopt advanced engineering techniques diffused from european cultures"

wood carving remains today the primary sculptural art form of the sub saharan continent. african art history shows the earliest wooden sculptures from the 17th c are attributed to the kuba, central zaire but the earliest surviving sub-saharan sculpture is a zoomorphic head found in 1928 in central angola.

i hope this .

b) brahmans   is nomadic society