Which statement would be the best final sentence in a conclusion on the topic of sand filter maintenance? a) the pump will cause water to flow from the pool through the hair and lint pot. eliminate b) set the pump on backwash whenever it needs to be cleaned with the cleaning process. c) the multiport valve on the pump controls the flow of water depending on the setting. d) over time the sand bed will become plugged with dirt and require a cleaning process known as backwashing