Which alternative should we choose? (5)

Alternatives always go in the Complication, because you ordinarily should not bring them up unless they are known in advance by the reader. That is, he will have identified them himself as possible courses of action that he wants you to weigh and analyze. What you specifically want to avoid is bringing up alternatives simply to knock them down. For example, "We have three ways we can solve this problem," with a Key Line that reads:

The reason for doing C is not that A and B are no good; the reason for doing C is that it solves the problem.