What type of circuit would use the principle of a voltmeter being connected in parallel?

A voltmeter is designed to measure the electrical potential difference between two points in a circuit, and it must be connected in parallel with the component across which the voltage is to be measured. This is because connecting it in parallel ensures that the voltmeter can accurately capture the voltage drop across the component without significantly altering the overall resistance of the circuit.

In a parallel connection, the voltmeter shares the same voltage as the component it is measuring, allowing for precise voltage readings. If you were to connect a voltmeter in series, it would introduce additional resistance into the circuit and could affect the operation of the circuit itself, leading to an inaccurate measurement.

Therefore, the correct identification of a circuit where a voltmeter is connected in parallel is a parallel circuit, making this answer appropriate.