Final answer:
The maximum fixture unit value when connecting fixtures to a circuit vent according to most plumbing codes is closely aligned with 10 units or 15 units. However, local regulations should also be checked.
Step-by-step explanation:
The question presents multiple choices referrring to the maximum fixture unit value when connecting fixtures to a circuit vent. From the given options, the correct answer isn't provided. However, according to the Uniform Plumbing Code (UPC) and the International Plumbing Code (IPC), the maximum limit is closely aligned with option c) 10 units, where two of the fixture units would add together to reach the maximum value or option d) 15 units, counting all units together. It's always best to check the specific plumbing code your jurisdiction follows for the most accurate information.
Learn more about Circuit vent fixture units