5. For solvent extraction, which of the following statements are correct? (1) For neutral analytes, many small extractions are less effective than few large extractions. (2) The larger the partition coefficient ([S]2/[S]1) of a neutral analyte, the less the analyte remain in phase 2. (3) To extract the base analytes into organic phase, use a pH high enough to convert BH into B.(4) To extract the acid HA into organic phase, use a pH low enough to convert A- into HA. (5) Most complexes that can be extracted into organic solvent are neutral, and charged complexes are less soluble in organic solvents. Your answer: (A) (1), (3) and (4)； (B) (2) and (3)； (C)(3), (4) and (5)； (D)(3) and (4)； (E) The statements are all correct.