Explanation:

MOSFET stands for Metal-Oxide-Semiconductor Field-Effect Transistor. It is a type of transistor that is widely used in electronic devices and integrated circuits.

Positive Temperature Coefficient:
A positive temperature coefficient means that the parameter or property of a device increases with an increase in temperature. However, a MOSFET does not have a positive temperature coefficient. In fact, the threshold voltage of a MOSFET typically decreases with an increase in temperature, resulting in a negative temperature coefficient.

High Gate Circuit Impedance:
The gate circuit impedance of a MOSFET is relatively high. This means that the input impedance of the MOSFET is high, allowing it to act as a voltage amplifier. The high gate circuit impedance allows for efficient switching and control of the MOSFET.

Voltage Controlled Device:
A MOSFET is a voltage-controlled device. This means that the output characteristics of the MOSFET, such as drain current and drain-source voltage, are controlled by the voltage applied to the gate terminal. By varying the gate voltage, the MOSFET can be switched on or off, allowing for the control of current flow through the device.

Correct Statement:
The correct statement is that "MOSFET is a voltage controlled device." This is true as the operation of a MOSFET is based on the voltage applied to its gate terminal. By controlling the gate voltage, the MOSFET can be used to amplify signals, switch currents, and perform various other functions in electronic circuits.

In conclusion, the correct statement is that "MOSFET is a voltage controlled device." This is because the MOSFET's operation is based on the voltage applied to its gate terminal. The other statements, such as MOSFET having a positive temperature coefficient or high gate circuit impedance, are not accurate.