Consider the following expressions which indicate the step or impulse response of an initially relaxed system [5 - 4 e-2t] u(t)[e-2t + 5] u(t)d(t) + 8 e-2t u(t)d(t) + 4 e-2t u(t) Those which correspond to the step and impulse response of the same system include

• A. 1 and 3
• B. 1 and 4
• C. 2 and 4
• D. 2 and 3