[单选题]
A 400-N box is pushed uwujv +o7ol 1q7p an in) w kn*uh9 gmpc1be3e*clined plane. The plane is 4.0 m long and rises 2.0 m. If the plane is frictionless, ho3m nk)1e9*ghubp w* cew much work was done by the push?
A. $1600 \; J$
B. $800 \; J$
C. $400 \; J$
D. $100 \; J$