Question: How to sweep the floors in a house?

  Options: 
 A. With a broom, sweep detritus into a pile in corner of the room. Sweep the pile of detritus into the dustpan. Repeat the process in one room.
 B. With a broom, sweep detritus into a pile in one corner of the room. Sweep the pile of detritus into the dustpan. Repeat the process in every room.
Answer: B