Which indian group lived in houses on stilts

The North American Tribe called The Mojave tribe lived in the Colorado River during Summer and Spring. They live in thatched huts raised of the ground by stilts.  Actually they lived in two different kinds of houses depending on the seasons.  In the summer and spring when they fished for existence, they stay in houses made up of wooden frame and covered with grass, raised on the ground with stilts. These would protect them from summer flooding.
In the winter and fall when they lived further from the Colorado River. They would live in earthen houses. The earthen houses were made of wooden frames but were packed with clay to keep the heat in. This was good for the cold winter and fall. These houses made good shelter for desert weather.

Answer b is the answet

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