Quiescent operating point, also known as the Q-point, is the operating point of a transistor or any electronic device when no input signal is applied. It represents the DC bias conditions of the device and is important for analyzing the device's behavior.

In the case of a transistor, the quiescent operating point is determined by the DC collector-emitter voltage (VCE), DC collector current (IC), and DC base current (IB). These parameters are essential in understanding the transistor's characteristics and ensuring proper operation. However, the DC input voltage (option D) is not considered for determining the quiescent operating point.

Explanation:
- DC Collector-Emitter Voltage (VCE): This is the voltage across the collector and emitter terminals of the transistor when no input signal is applied. It is an important parameter in determining the operating region of the transistor (active, saturation, or cutoff) and affects the transistor's gain and power dissipation.

- DC Collector Current (IC): This is the current flowing through the collector terminal of the transistor when no input signal is present. It is a crucial parameter in determining the transistor's output characteristics, power dissipation, and operating region.

- DC Base Current (IB): This is the current flowing into the base terminal of the transistor when no input signal is applied. It is necessary for biasing the transistor and establishing the necessary conditions for proper operation.

- DC Input Voltage: The DC input voltage is not directly considered for determining the quiescent operating point. It typically refers to the voltage applied to the base-emitter junction of the transistor. While the base-emitter voltage is relevant for biasing the transistor, it does not directly define the quiescent operating point.

In summary, the DC input voltage is not considered for determining the quiescent operating point. Instead, the DC collector-emitter voltage, DC collector current, and DC base current are the key parameters considered.