Emphatic stress is the placement of greater stress on a particular word or syllable in a sentence or utterance. The rule is to select a question from the options that is similar to the sentence above except for the word in capital letters. Option D is the answer to this question because the sentence is the appropriate response to the question as it aims to clarify the misapprehension in the question. It is not my sister but rather, YOUR sister that should come with us tomorrow.