Final answer:
The development of irrigation systems supported highly productive agriculture in the desert southwest.
Step-by-step explanation:
The agricultural technology or advancement that supported the desert southwest becoming suitable for highly productive agriculture was the development of irrigation systems.
With the help of irrigation systems, water could be directed to the arid regions of the desert southwest, allowing for the growth of crops such as corn, squash, and beans.
One example of an ancient irrigation system used in the desert southwest is the Hohokam's canal system, which transformed vast areas of the region into fertile farmland.
Learn more about Irrigation systems in the desert southwest