The correct answer is positive fee back.
Positive feedback is termed as the process which appears in a feedback loop whereby small disturbance on a system may leads to increase in magnitude.
There is exponential growth when the side of equilibrium increases in oscillation. Positive feedback is used in digital electronics which moves voltage away from intermediate voltage.
Another example of positive feedback is thermal runaway and its work is to destroy semiconductor junctions. In chemical reaction the work of positive feedback is to increase the rate of reaction.
