A Answer A is correct. A leak in an A/C hose is usually indicated by an oily spot on the hose.

B Answer B is wrong. When oil is lost in a system or a part has been replaced it is necessary to replace the oil to the proper level.

C Answer C is wrong. Technician A is correct.

D Answer D is wrong. Technician A is correct.

A Answer A is wrong. Mineral oil doesn't mix with 134a it is used with R-12: 134a uses PAG Polyalkaline Glycol or Polyol Ester.

B Answer B is correct. A/C oils mix with the refrigerant to lubricate the compressor, seals, o-rings, etc. in the system.

C Answer C is wrong. Technician B is correct.

D Answer D is wrong. Technician B is correct

A Answer A is wrong. This is an except question.

B Answer B is wrong. This is an except question.

C Answer C is correct. An overtightened A/C compressor belt can damage the pulley bearings.

D Answer D is wrong. This is an except question.

A Answer A is wrong. A frozen point on an A/C component or connection indicates a restriction in the system.

B Answer B is wrong. A frozen expansion valve will cause a low-low side pressure.

C Answer C is correct. Both technicians are correct.

D Answer D is wrong. Both technicians are correct.

A Answer A is wrong. The temperature cycling clutch switch uses a bulb placed on the outlet port of the evaporator core.

B Answer B is correct. A typical pressure cycling switch is located on the accumulator or the low side of a system.

C Answer C is wrong. Technician B is correct.

D Answer D is wrong. Technician B is correct.