Find the derivative.

$s=sint-e^{-1}$

$$ A$.\frac{ds}{dt}=-cost-e^{-t}$

B$.\frac{ds}{dt}=cost-e^{-t}$

c$.\frac{ds}{dt}=-cost{e}^{-t}$

D$.\frac{ds}{dt}=cost{e}^{-t}$