When servicing a small appliance found to be leaking, it is:

A. Not mandatory to repair the leak, but it is recommended to do so whenever possible.
B. Optional to repair the leak, with no impact on appliance functionality.
C. Mandatory to repair the leak, but only if it affects the appliance's performance.
D. Discouraged to repair the leak unless explicitly instructed in the manual.

It is mandatory to repair a leak in a small appliance if the leak affects its performance, due to potential safety risks, efficiency issues, and compliance with regulations. Therefore, the correct answer is c. Mandatory to repair the leak, but only if it affects the appliance's performance.

Explanation:

When servicing a small appliance that is found to be leaking, it is mandatory to repair the leak, but only if it affects the appliance's performance. This is because any leakage could pose a variety of issues, including safety risks, reduced efficiency, and potential further damage to the appliance.

Also, ignoring a small leak can lead to bigger problems in the future, potentially increasing the cost and complexity of the repair. Moreover, depending on the nature of the appliance and the substances involved, there might be environmental regulations or health and safety standards that require leaks to be fixed promptly.

When servicing a small appliance found to be leaking, it is mandatory to repair the leak, but only if it affects the appliance's performance.