The state-variable representation of a plant is given byẊ = Ax + Buy = CxWhere x is the state, u is the input and y is the output. Assuming zero initial condition, the impulse response of the plant is given by

• A. exp(At)
• B. \(\smallint \exp \left[ {A\left( {t - \tau } \right)} \right]Bu\left( \tau \right)d\tau\)
• C. C exp(At)B
• D. \(C\smallint \exp \left[ {A\left( {t - \tau } \right)} \right]Bu\left( \tau \right)d\tau\)