Final answer:
In the Exact-O-Pour test, a successful pour must be within A) 1/4 oz. of the target amount, ensuring precision in serving drinks and controlling costs for establishments.
Step-by-step explanation:
When completing the Exact-O-Pour test, a successful pour is within 1/4 oz. of the desired shot.
This means that when bartenders or servers are testing their ability to pour exact quantities of liquid, typically for the purpose of serving alcoholic beverages, they are expected to have a very high level of precision.
This precision ensures consistency in the drinks served to customers and helps to control costs for the establishment.