And comparing a desert to on Mars which statement is not true

You didnt exactly put in any answer options ...

But here is my answer: Comparing a desert to Mars, i would say that

A desert has oxygen

And mars has carbon dioxide

A desert has sand

Mars has a rocky surface

Mars is a planet

A desert is not

The things i could think of that a desert and planet mars can relate to ... I would say they both have heat and both sometimes have dust storms.