Answer : D. It's up to you to decide what to do.
Based on the choices above, only the sentence in letter D is using apostrophe correctly. An apostrophe is a punctuation mark which refers to the possession of something such Trisha's bag or it also marks the omission of certain letters or numbers within a word. In the sentence in letter D, it can be seen that the apostrophe is used to omit the "i" in the word "is" joining it to "It" creating the word "It's".
