TOEFL Reading: ETS-TOEFL阅读机经 - FTY6GCPE9U6_65KDL$

According to paragraph 1, why was Memphis a better choice for the capital of a united Egypt than either This or Hierakonpolis? A. Memphis was in a better location for maintaining administrative control. B. Memphis had long been a regional administrative center by the time Egypt was united. C. This and Hierakonpolis had never actually been incorporated into the unified state. D. Egyptian rulers had failed to keep political control over This and Hierakonpolis in predynastic times.