If 0 < st < 1, then which of the following can be true?

a.) s < -1 and t > 0

b.) s < -1 and t < -1

c.) s > -1 and t < -1

d.) s > 1 and t < -1

e.) s > 1 and t > 1

The answer is c.)... how?

If s > -1, that means s = 0, 1, 2, ...

If t < -1, that means t = -2, -3, ...