Explanation: In a shunt-fed plate circuit, the RF choke (RFC) is designed to present a high impedance to radio frequency (RF) signals, keeping them within the plate tank circuit, while offering a low impedance to direct current (DC) to power the vacuum tube's plate. If the plate RF choke shorts: * **A) The plate tank circuit would be effectively shorted:** A shorted choke provides a very low impedance path directly across the plate (via the DC blocking capacitor) to the B+ supply. This bypasses and effectively shorts the parallel resonant plate tank circuit, preventing it from developing the necessary high RF voltage. * **B) The DC plate current would increase, possibly to excess:** With the tank circuit shorted, the amplifier tube "sees" a very low impedance load. This causes the tube to draw a much higher DC plate current than normal, potentially exceeding its maximum ratings and causing damage to the tube or power supply. * **C) No RF output could be expected:** Since the plate tank circuit is shorted, it cannot resonate or develop any RF voltage. Without RF voltage swinging at the plate, no RF power can be coupled to the antenna, resulting in no RF output. Therefore, all the listed consequences occur when the plate RF choke in a shunt-fed circuit shorts.