The most likely reason Pueblo constructed most of their buildings out of adobe is because Pueblo typically lived in areas where adobe was more readily available over other building materials.
Pueblos are modern and old communities of Native Americans in the Southwestern United States. The first Spanish explorers of the Southwest used this term to describe the communities housed in apartment-like structures built of stone, adobe mud, and other local material.
The correct answer between all the choices given is the second choice or letter B. I am hoping that this answer has satisfied your query and it will be able to help you in your endeavor, and if you would like, feel free to ask another question.