Answer:
b. moving to the top of a mesa.
Explanation:
By 1050, Pueblos had developed apartment-house villages with a defensive strategy on the on steep-sided mesas that can protect the Puebloans from the attack of the north parties.
Pueblos move to the top of the mesas and constructed apartment-house and more high is the apartment-house more protected the place it was.
Hence, the correct answer is "b. moving to the top of a mesa."
