Question

Due to lack of _______ to use for building cabins, many of the prairie home were made of ___________?

Answer 1

The answer would be #3
Due to lack of trees to use for building a cabin, many of the prairie homes were made of sod.

Answer 2

Hi!

There weren't many trees around, but there was a lot of sod. Sod is the top part of the ground with the grass.

So the answer is 

Due to lack of trees to use for building cabins, many of the prairie homes were made of sod.

Hope this helps! :)