Final answer:
Both Technician A and Technician B are correct.
The correct answer is: option 'Both A and B'.
Step-by-step explanation:
Technician A and Technician B are discussing the recommended oil for different air conditioning systems.
Technician A is correct when they say that the recommended oil for most R-134a systems is PAG oil. PAG oil is a synthetic oil that is specifically designed to work with R-134a refrigerant, which is commonly used in modern air conditioning systems.
On the other hand, Technician B is also correct when they say that the recommended oil for R-12 systems is mineral-based oil. R-12 refrigerant was commonly used in older air conditioning systems, and mineral-based oil is compatible with it.
Therefore, the correct answer is that both Technician A and B are correct.