__ a member of the CFC family of gases, was the first common refrigerant to be used in an automotive air conditioner. a. HFO -1234yf b. R-134a c. R-12 d. R-410a

## Step 1<br />The problem is asking us to identify the first common refrigerant used in automotive air conditioning from the given options. The options are HFO-1234yf, R-134a, R-12, and R-410a.<br />## Step 2<br />The CFC (Chlorofluorocarbon) family of gases includes R-12, which was the first common refrigerant used in automotive air conditioning.<br />## Step 3<br />The other options, HFO-1234yf, R-134a, and R-410a, are not CFCs and were not the first common refrigerants used in automotive air conditioning.