A Tractor T Is Pulling Two Trailers, M₁ and M₂

Multiple Choice

A tractor T is pulling two trailers, M₁ and M₂, with a constant acceleration. T has a mass of 200 kg, M₁ has a mass of 100 kg, and M₂ has a mass of 150 kg. If the forward acceleration is 0.60 m/s², and air resistance is negligible, then the horizontal force on the tractor due to the attachment to M₁ is

A) 270 N backward.
B) 270 N forward.
C) 150 N backward.
D) 150 N forward.
E) 90 N forward.