Which of the following statements is NOT a reliable way to identify a light-emitting diode (LED) based solely on its energy band gap?

(a) LEDs typically have a wider band gap than regular diodes.
(b) LEDs require a specific energy band gap for efficient light emission.
(c) All materials with a wider band gap than silicon can be LEDs.
(d) The material composition of the diode can be used to predict its suitability for light emission.