请选择DCBA:f-]+E2K(p;U(r+{/c __________look__________the blackboard．7W,q.M+Y'D)g
A．Let， at7W,q.M+Y'D)g
B．Let' s， at7W,q.M+Y'D)g
C．Lets， like7W,q.M+Y'D)g
D．let， on7W,q.M+Y'D)g