which option accurately describes an unbalanced force?

A) Each cement block supports a2-N force, but when the foundation is built in a staggered pattern it can support 2,000 N

B) Three rows of cement blocks form a foundation for a house, and the house rests on this foundation

C) A 2-N force presses down on the cement block at the same time as a 1.5-N force presses up on the cement block

D) the force of a house pressing down on its foundation of cement blocks is 3,000 N.