Answer:
The correct option is D
Step-by-step explanation:
Zone of tolerance is described as the perception of customer range of the service among the minimum as well as the desired acceptable standards. In short, it is described as the lowest level of the performance which customers will accept.
It is the area among the desired service and the adequate service which is acknowledged as the zone of tolerance and state the range of the service performance which customers could tolerate.
So, in this case, it is the zone of tolerance which is the difference among the what the customers desire and what they accept before going elsewhere.