ANS:B - outfall sewer

The sewer that unloads sewage at the point of treatment is typically referred to as an outfall sewer. Explanation:

• Main Sewer: Main sewers are large-diameter pipes that receive wastewater from various branch sewers and convey it to a treatment facility or a point of discharge. They serve as the primary conduits for transporting sewage within a municipal sewer system.
• Branch Sewer: Branch sewers are smaller pipes that collect wastewater from individual properties or smaller areas and convey it to larger main sewers. They branch off from main sewers and help to distribute sewage flow throughout the sewer network.
• House Sewer: House sewers, also known as lateral sewers or building sewers, are pipes that connect individual buildings or properties to the municipal sewer system. They carry wastewater from homes, businesses, or other structures to the public sewer network.
• Outfall Sewer: An outfall sewer is a sewer that carries sewage to the point of discharge, which could be a treatment plant, a sewage outfall into a water body (such as a river, lake, or ocean), or another appropriate disposal point. The outfall sewer serves as the final conduit in the sewer system, where sewage is released for treatment or disposal.