In the figure, the blocks A,B and C of mass m each have accelerations `a_(1),a_(2)` and `a_(3)` respectively. `F_(1)` and `F_(2)` are external forces of magnitude 2mg and mg respectively.
A. `a_(1) = a_(2) = a_(3)`
B. `a_(1) gt a_(3) gt a_(2)`
C. `a_(1) = a_(2), a_(2) gt a_(3)`
D. `a_(1) gt a_(2),a_(2) = a_(3)`
