What will happen if some cabbage white butterflies mate

Question

my brother cought some cabbage white butterflies while they where mating what will happen next

Answer 1

humpty humpity makes babbies

Answer 2

butterflies lay eggs on a food source (cabbage, lettuce, leafy greens) the eggs hatch into  caterpillars (lopers) which eat the food source then they will form a chrysalis.  Eventually they will emerge form the chrysalis as cabbage white butterflies.

Answer 3

they will make babbies.

butterflyes make callowpillar babbies

Answer 4

If they remain on cabbages they make cabbage lopers which destroy your cabbage.