单项选择题
A.y[n-3]=x[n-3]*h[n]B.y[n-3]=x[n-3]*h[n-3]C.y[n-3]=x[n]*h[n-3]D.y[n-3]=y[n]*\delta[n-3]
A.z=x*yB.z=x.*yC.z=x’*yD.z=x*y’
A.20B.7C.7/20D.20/7