Michael is writing a response to his classmate on the discussion board. He copies and pastes some material from textbook into his response and he put an in-text citation immediately after it. He meant to put the material from the textbook in quotation marks but he forgot. He remembered to include the reference for the textbook, though. This is:

a. Just a small formatting error because he remembered to include the in-text citation and reference.
b. Plagiarism because without quotation marks Michael is indicating that all of the words in the response are his when he has used the textbook author's words.
c. Not a big deal because it's unlike that the instructor will notice or check.