D1: The Hasse diagram for the partial ordering {<a, b> |a mod b=0} on the set of {positive divisor of 24}
Set of positive divisor of 24 = {1,2,3,4,6,8,12}
D2: The Hasse diagram for the partial ordering {<a, b> |a mod b = 0} on the set of {positive divisor of 81}
Set of positive divisor of 81={1,3,9,27,81}
So, D2 is total ordering while D1 is not! Answer: B