What term is used to describe many operational amplifier (op-amp) circuits?

The term used to describe many operational amplifier (op-amp) circuits is inverting. An inverting op-amp circuit is characterized by its ability to produce an output voltage that is 180 degrees out of phase with the input voltage. In this configuration, the input signal is applied to the inverting terminal through a resistor. The feedback resistor connected from the output to the inverting terminal determines the gain of the circuit while the non-inverting terminal is typically grounded.

This configuration is fundamental in op-amp applications and is widely used because it allows for various signal processing tasks such as amplification, filtering, and signal manipulation. The inverting nature allows for precise control over the gain and the output signal behavior, which makes it a practical choice in many electronics applications. The other options, while they might describe specific configurations of op-amps, do not represent the broad category of circuits that many operational amplifiers are associated with.