Xiao Zhang scores better than Xiao Li, but because Xiao Ming scores better than Xiao Hong, Xiao Zhang scores better than Xiao Hong. Except for the following, all are OK. As a necessary prerequisite for the above statement to hold? ['Xiao Zhang and Xiao Ming score equally well.', 'Xiao Li has better grades than Xiao Hong.', 'Xiao Zhang scores better than Xiao Ming.', 'Xiao Ming has better results than Xiao Zhang.']