Fly on a direct path from the planet to the moon burning rockets all the way

Fly in an elliptical orbit with a periapse (closest approach to body around which we orbit) of the distance at which we orbit the planet initially, and an apoapse (farthest approach to body around which we orbit) of the distance at which the moon orbits the planet.

Fly in an elliptical orbit with a periapse (closest approach to body around which we orbit) of the distance at which we orbit the planet initially, and an apoapse (farthest approach to body around which we orbit) of twice the distance at which the moon orbits the planet.

Fly in an elliptical orbit with a periapse (closest approach to body around which we orbit) of the distance at which we orbit the planet initially, and an apoapse (farthest approach to body around which we orbit) of half the distance at which the moon orbits the planet.