When is a modifier misplaced? when it seems to apply to the wrong word

when it is used with the wrong tense

when it is too far from the noun

when it comes after a conjunction

A misplaced modifier is a word, phrase, or clause that is improperly separated from the word it modifies / describes. Because of the separation, sentences with this error often sound awkward, ridiculous, or confusing. Furthermore, they can be downright illogical.

Explanation:

halibut, flounder, tuna, and trout are all fish. so your first answer is 1.) fish. and since fish is edible, your next answer would be 3). edible

to describe those fishes more thoroughly, some of those fishes live in fresh water, and some of the fishes live in salt water, and that is not a thing that they all have in common. the question is asking what is common with all of the fish, so answer choices 2). fresh water and 4). salt water are not right.