DNA<span> is </span>made<span> up of six smaller </span>molecules<span> a five carbon sugar called deoxyribose, a phosphate </span>molecule<span> which contains these four (adenine, thymine, cytosine and guanine).</span>
All of the other answers share at least one factor they can be divided by (the numerator in all cases). 5/12 however shares no factors and cannot be simplified anymore.
