Which of the following statements about diodes and triodes is correct? a. adjusting the grid within a diode will have more of an effect than it will in the triode. b. triodes have three electrodes, whereas diodes have only a grid and a cathode. c. diodes are often utilized as amplifiers, whereas triodes are often used as rectifiers. d. diodes, which are often utilized as rectifiers, have two electrodes.

The correct answer is D.
Diodes, are often utilized as rectifiers, have two electrodes.
A diode which means two has two electrodes which are anode and cathode. Electrons are being shot in cathode-anode attracts when the voltage is being applied.
Triode means three and it has three electrodes in the vacuum which include grid, anode and the cathode. Grid and cathode offset voltages with a small variation of input. Large variations of the anode will be inflicted by grid voltage within a process called amplification.

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