Pushing an empty refrigerator box down an icy path
Objects with more weight have more frictional force; thus, moving that heavier objects requires greater force. Additionally, the icy path has a lower coefficient of friction than the regular path. Because of these factors, the empty box on the icy path will be the easiest to move.
B Pushing an empty refrigerator box down a path
C Pushing a refrigerator in its box down a path
D Pushing a refrigerator in its box down an icy path