Given the transfer function G(s) of a system (3s+7)/(s(s+1)) A unit step u(t) is applied to the system’s input, then the time response y(t) is()
A.y(t)= u(t) · (4+7t+4 e-t) B.y(t)= u(t) · (2 + 7t + 7e-t) C.y(t)= u(t) · (7 +4t + 4e-t) D.y(t)= u(t) · (4 – 2t + e-t)