Can Someone Please Explain This Silent Marshes Puzzle To Me?

Because I have no idea. Alright, so here's a picture of the puzzle.

Clear enough what you're supposed to do, right? Hit the keys in order, matching the image next to the number to a related image on a key. Couldn't be simpler, right? So let's go over them-

1 - Match the Sun to the Flower.
2 - Match the Spider to the Fly.
3 - Catch the Chicken to the Egg.
5 - Match the Wave to the Boat.

Which brings me to '4'. By process of elimination, I know where the bat goes with key number 2, but what the hell is that? An onion? A fist of garlic?

That's the closest I could come to, but I'm still baffled by it - you know that garlic has no associations with bats, right? It's just vampires that are afraid of garlic, not bats. It's just puzzling, especially since there's no trend making them clear.

Suns feed flowers. Spiders eat flies. Hens lay eggs. Boats ride on waves. Bats... are afraid of garlic?

So strange.