Which native american tribe lived in an arid climate region and built permanent apartment-like structures out of mud and hay?

the us constitution is a living document, meaning that it can be changed over time as the country changes.

the answer to your question is a. the salt plains

in 1811, he led an expedition, known as the george c. sibley expedition, to improve relations with the pawnee and kansa tribes, and also to locate the rumored jefferson's salt mountain