The main idea of the third paragraph is that ______.A．a mature torpedo is capable of produ

The main idea of the third paragraph is that ______.

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