Sentences 15 and 16; the plankton attract small fish. the small fish attract larger fish. the most effective combination of sentences 15 and 16 would include which group of words?

Example:
The plankton attract larger fish.

Hey there!

The most effective combination of these two sentences would probably be:

"The plankton attract the smaller fish, which attract the larger fish."

You could also use a transition to make it a little fancier:

"The plankton attract the smaller fish, which in turn attract the larger fish."

"The plankton attract the smaller fish, which then attract the larger fish."

I don't know what "group of words" your question could be referring to, but if you have answer choices, let me know and I'd be happy to help you out further!

Either way, hope this shed at least some light on your question! :-)