The correct answer is: A. Enhancement mode
An inverter is a circuit that converts a signal from one logic level to the other. It is a basic building block in digital electronics and is used in a variety of applications, such as logic gates, flip-flops, and counters.
The most common type of inverter is the NMOS inverter, which uses an N-channel MOSFET as the load. The MOSFET is a type of transistor that is controlled by a voltage applied to its gate. When the gate voltage is high, the MOSFET is turned on and the output voltage is low. When the gate voltage is low, the MOSFET is turned off and the output voltage is high.
The NMOS inverter is a simple and efficient circuit that is widely used in digital electronics. It is also relatively easy to understand and implement.
Depletion-mode MOSFETs are not typically used as loads in inverter circuits because they require a positive gate-source voltage to turn on. This can cause problems in some applications, such as when the inverter is used to drive a high-impedance load.
All of the mentioned is not the correct answer because only enhancement-mode MOSFETs are typically used as loads in inverter circuits.