Two discrete-time linear time-invariant systems with impulse responsesh1[n] = δ[n - 1] + δ[n + 1] and h2[n] = δ[n] + δ[n - 1] are connected in cascade, where δ[n] is the Kronecker delta. The impulse response of the cascaded system is

• A. δ[n - 1] δ[n] + δ[n + 1] δ[n - 1]
• B. δ[n - 2] + δ[n + 1]
• C. δ[n - 2] + δ[n - 1] + δ[n] + δ[n + 1]
• D. δ[n] δ[n - 1] + δ[n - 2] δ[n + 1]