Question

read the passage.
when sea slugs are in need of something to eat, they often turn to an unusual food source: jellyfish. although jellyfish can be deadly, scientists hypothesize that sea slugs keep themselves safe by using slime to cover the cells responsible for delivering a jellyfishs stings. but why go through the trouble of eating such a hazardous snack? well, after the slug swallows the jellyfish, it doesnt digest the stinging cells. instead, the cells move toward the sides and back of the slugs body. then, if a fish tries to eat the sea slug, it will be stung by the new toxic cells! it turns out jellyfish arent only a meal for sea slugs; theyre also a way for sea slugs to avoid becoming a meal themselves.
what is the main, or central, idea of the passage?
sea slugs can consume toxic jellyfish cells and use them for their own protection.
some fish avoid being eaten by sea slugs by stinging them with toxic cells.
because they consume jellyfish, sea slugs are an attractive prey to many fish.
sea slugs can do many unexpected things with their bodies in order to survive.

Explanation:

The passage focuses on sea slugs eating jellyfish, retaining their stinging cells, and using those cells to avoid being eaten by other fish. The first option directly matches this core idea. The second option reverses the predator-prey relationship. The third option contradicts the passage, as sea slugs use the cells to avoid being prey. The fourth option is too broad; the passage only details one specific survival adaptation, not multiple unexpected body uses.

Answer:

Sea slugs can consume toxic jellyfish cells and use them for their own protection.