A Tractor $T$ Is Pulling a Trailer $M$ With a Constant Acceleration $0.50 \mathrm{~m} / \mathrm{s}^{2}$

Multiple Choice

A tractor $T$ is pulling a trailer $M$ with a constant acceleration. If the forward acceleration is $0.50 \mathrm{~m} / \mathrm{s}^{2}$ and $M$ $=400 \mathrm{~kg}$ and $\mathrm{T}=500 \mathrm{~kg}$ , then the horizontal force on the tractor due to the ground is (ignore air resistance)

A) $450 \mathrm{~N}$ backward.
B) $250 \mathrm{~N}$ forward.
C) $200 \mathrm{~N}$ forward.
D) $250 \mathrm{~N}$ backward.
E) $450 \mathrm{~N}$ forward.