Introduction:
IGBT stands for Insulated Gate Bipolar Transistor. It is a three-terminal power semiconductor device that combines the advantages of a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) and a bipolar junction transistor. IGBTs are widely used in various applications such as motor drives, power supplies, renewable energy systems, and electric vehicles.

Explanation:
The correct answer is option 'B' - IGBTs possess high input impedance. Let's understand why this is the case and explore the other options as well:

1. Low input impedance:
IGBTs actually have high input impedance. The input impedance of a device refers to its ability to draw current from the input signal source. In the case of IGBTs, they have a high gate impedance, which means that they require very little input current to control the device. This high input impedance allows IGBTs to be easily driven by low-power control signals.

2. High input impedance:
As mentioned earlier, IGBTs have high input impedance. This means that they do not draw much current from the control signal source, making them suitable for applications where the control signal source has limited current capability.

3. High on-state resistance:
IGBTs typically have relatively low on-state resistance. This is one of the key advantages of IGBTs compared to other power devices such as power MOSFETs or bipolar transistors. The low on-state resistance allows IGBTs to handle high currents with minimal power losses, resulting in improved efficiency of power electronic systems.

4. Second breakdown problems:
IGBTs are designed to handle high voltages and currents. They are less prone to second breakdown problems compared to bipolar transistors. Second breakdown is a phenomenon that occurs when excessive current causes localized heating in the device, leading to thermal runaway and device failure. IGBTs are inherently more robust and have better thermal characteristics compared to bipolar transistors, reducing the risk of second breakdown.

Conclusion:
In summary, IGBTs possess high input impedance, making them suitable for applications where the control signal source has limited current capability. They also have low on-state resistance, which improves the efficiency of power electronic systems. Additionally, IGBTs are less prone to second breakdown problems compared to bipolar transistors, making them a preferred choice for high-power applications.