The ideal title for this passage is（）

A．the working system of the electric plates in the eel is the most effective
B．the working system of the electric plates in the eel is far inferior to those in the torpedo
C．compared with those in the torpedo, the working system of electric plates in the eel is more direct and efficient
D．compared with other electric fish, the eel possesses much more electric plates

A．a mature torpedo is capable of producing enough electricity to knock down a man
B．the mass of the fish decides the intensity of electric power it generates
C．the strength of shock given by a young electric ray can only light the bulb of a pocket flashlight
D．to make full use of the energy produced by electric fish, suitable wires should be available