Which type of punctuation signals the reader that words from a direct quotation have been changed by the writer?

Of the options presented in the problem, the answer that would likely to be correct would be the second one which would be brackets.

Punctuations are very important and some, if not many, don't understand the other punctuations when used and it is important to understand it, may it be as a reader or as a writer. Parentheses are used when there is an additional explanation to a statement or phrase or just to add a remark on what was stated before it. Ellipses, on the other hand, are used when there are words, phrases, or even sentences that are omitted due to the author's / writer's personal reasoning. This might be intended to create an atmosphere suited for the particular part of the story or something else. Quotation marks are used when direct quotations are used, jargons are utilized, the word or words are being discussed, or it is the title.