The correct answer in the statement above is letter C, keeping sentences uniform in length. It is because this will motivate readers to read if the sentences has the right amount of words where they could understand enough and to get them reading. If it is too short, they won't understand what they're reading and if it is too long, it will only make them find less interest in what they are reading, that is why it is important to make it uniform in length for it to be readable.