 Which term best describes Mars' population?
The planet itself was tough enough—barren, desolate, forbidding; enough to stop the most adventurous and dedicated. But no; she blamed it all on me somehow: So we were out walking on the spongy sand of the Martian desert. She had been just as much inflamed by the idea of coming to Mars to help in the search for uranium as I was. No, we had decided together to come to Mars—the way we decided together on everything. I watched her, sleeping peacefully, a wayward lock of her soft blonde hair trailing down over one eyebrow, and it seemed hard to believe that we'd exchanged Earth and all it held for us for the raw, untamed struggle that was Mars. I thought I knew everyone on sparsely-settled Mars.
 meager
 congested  meager  sustainable  uninhabited