A class C mine must have at least what combination of safety personnel?

In a class C mine, the safety requirements are such that there needs to be adequate oversight and compliance with safety regulations. The option specifying 1 part-time safety inspector and a deputy inspector meets the regulations needed for a class C mine, as it allows for the necessary safety checks without requiring full-time personnel.

Having a part-time safety inspector ensures that there is someone assigned specifically to oversee safety protocols and regulatory compliance, while the deputy can assist with these duties and provide additional support. This combination can be effective in maintaining safety standards, especially in a class C mine environment where the operational scale may not necessitate a full-time commitment from a safety engineer or a full-time safety inspector.

The other options suggest higher requirements for personnel that may not align with the specific criteria for class C mines, where resources may be allocated differently based on the operational capacity and potential risks.