What choice does Zaroff give to Rainsford, and why is there really no choice at all?

General Zaroff gives Rainsford a choice between two awful potentials.  Zaroff explains to Rainsford that he gives the men that are trapped on his island a choice.  They can either be whipped to death by Ivan, or they can attempt to survive Zaroff's hunting for three days.  General Zaroff gives Rainsford the exact same choice.  

For most men, the choice really isn't a choice at all.  Thus far, no matter what each man chooses, the end result has been the same.  Death.  The only difference is that choosing to be hunted might give a man a few extra hours of life.  Rainsford chooses to take his chances on the hunt instead of a guaranteed death from Ivan.  Rainsford's choice winds up being a good choice for Rainsford because Rainsford evades Zaroff and eventually ends up killing Zaroff.