According to CPC Chapter 10, each plumbing fixture must be separately trapped. Under what condition may one trap serve multiple fixtures?

• One trap may serve all fixtures in a residential bathroom group.
• One trap may serve fixtures if they drain to a common waste line of 3 inches or larger.
• One trap may serve any two fixtures of the same type on the same floor.
• One trap may serve up to three sinks or laundry tubs in the same room within 30 inches of each other.