I believe it is A. because it says they will take and i believe take is a verb and its worded in future tense
Based on the given sentence above, the error that I can find is the incorrect use of the pronoun "their". Looking at the sentence, the subject is "One of your students", this means only one, and not all the students. Therefore, this should take a singular pronoun. So the correct sentence would be "One of your students left his or her book on the table." So the answer for this would be option A. Hope this helps.
