The correct answer to this open question is the following.
The author includes the section "Living Off the Land" to explain how possible Mars's residents have important things to do if they want to settle Mars and establish a human colony on the Red Planet.
What the author specifically does is to present the problem and solution approach in this part of his work.
It shows what the problems are, followed by the possible solutions for those problems. To settle Mars has been one of the permanent challenges of scientists and astronauts. It seems so far away, but recent research has developed many theories on how humans could establish a colony in the future.
