TG EAMCET 3 May 2025 Shift 2 Paper

From the graph
In region I, output voltage is high as V0 when the input voltage Vi is low. i.e., transistor is off. This is cutoff region.
In region II, output voltage decreases as input voltage increases. This is the situation when transistor operates as an amplifier.
Thus, in region II, transistor is in active mode.
In region III, output voltage is low when input voltage is high i.e., maximum current flow through the collector. Thus, transistor is in saturation region.