A barbecue sauce producer sells their product in a 18-ounce bottle. Their current process mean is 17.8 ounces with a standard deviation of 0.20 ounces. If their tolerance limits are set at 18 ounces plus or minus 1 ounce, what is the process capability index/ratio of the bottle filling process?

Group of answer choices

0.91

1.0

1.33

2.0