The correct answer is - c: military men prepared to survive in the wilderness.
The first settlers in Jamestown were all men, young and middle aged. They were all tough men, and had more or less some military experience. So it was expected that they can survive in the New World without any significant problems, but it is not how things evolved. The settlers just weren't able to adapt to the new environment, diseases were very common and lots of them died, they were not familiar with the local plants, nor were very knowledgeable of the weather, so for most of the time they were starving. The only reason why the colony didn't failed very quickly were actually the natives that were helping the new settlers and were providing enough food for them so that they can survive.