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Which of the following statements about the intermediate treatment process is incorrect? A. In a reclaimed water system that uses wastewater from bathing as its source water, a hair filter should be installed on the suction pipe of the sewage pump. B. Domestic wastewater used as a source for reclaimed water should be treated in a septic tank first. C. Kitchen wastewater must undergo sedimentation treatment before it can be fed into the reclaimed water system. D. When the amount of sludge generated during reclaimed water treatment is small, it can be discharged to a septic tank for treatment. Answer: C. Option A complies with the provisions of Article 6.2.4 of the \"Code for Design of Reclaimed Water in Buildings\". The bath water contains a large amount of hair fibers. Racks alone cannot effectively trap hair; considering the safety of equipment operation, it is specified that a hair collector must be installed on the pump’s suction pipe. Option B complies with the provisions of Article 6.2.2 of the Code for Design of Reclaimed Water in Buildings. When domestic wastewater is used as a source for reclaimed water, a septic tank can be regarded as a pre-treatment facility for reclaimed water treatment. To prevent water containing a high amount of solid suspended matter from clogging the raw water collection pipes and wastewater treatment equipment, domestic sewage should be treated in septic tanks. Option D complies with the provisions of Article 6.1.8 of the Code for Design of Reclaimed Water in Buildings. When the amount of sludge is small, using mechanical dewatering equipment is costly; therefore, the anaerobic fermentation by microorganisms in the septic tank can be utilized for its removal. Option C does not comply with the provisions of Article 5.2.5 of the Code for Design of Reclaimed Water in Buildings. According to the requirements of this standard, kitchen wastewater must undergo oil separation before it can be discharged into the main drainage system; option C incorrectly uses sedimentation as the treatment method