A sea anemone because they have a symbiotic relationship. The clown fish is kept safe when in the sea anemone from predators. They clown fish also eats the left overs on a sea anemone! :)
D) laboratory experiments because every experiment needs a control and a variable.
Answer: (B) Prothallus
Explanation: Prothallus is the gametophyte stage in the life of <u>a fern or other pteridophyte</u>.