When the graph of current versus voltage is a straight line, the device is referred to as A. Active B. Linear C. Nonlinear D. Bipolar E. None of the above

An active device is a device that can amplify a signal. This means that it can take a small input signal and produce a larger output signal. Active devices are often used in amplifiers, oscillators, and other electronic circuits.

A bipolar device is a type of transistor that has two types of charge carriers: electrons and holes. Bipolar transistors are often used in amplifiers and switching circuits.

None of the above is not a correct answer.