Game of Chess

Ned and Jon are playing chess. Eventually, they end up in a position in which Ned (whites) is left with 2 rooks, and Jon (blacks) has just his king on the board. If Ned can mate Jon in exactly 4 different ways, what is the position of the pieces?

Black king on a1, white king on e5, white rooks on c2 and h1. Ned hasn't moved his king and rook, so he can either castle or move his king to d2, e2 or f2, resulting in a mate.