The correct answer is C. <span>Emily loves to noisily and cheerfully make breakfast for her family each day. A split infinitive refers to the fact that there is a word included between the word TO and the verb. That word should not be there because it makes the infinitive to split itself into two parts. So here, as you can see, words <em>noisily and cheerfully </em>make a split between the word TO and verb make breakfast, which shouldn't be done. </span>
It makes the reader wonder who the author is talking about when she says “they”. Both sentences are describing a type of person. The reader is meant to question themselves.