A . 肠系膜下静脉→直肠静脉丛→髂内静脉→下腔静脉
B . 脐静脉→脐周腹壁静脉→腹上静脉→乳内静脉→上腔静脉
C . 胃冠状静脉→食管下静脉→奇静脉→上腔静脉
D . 肠系膜上静脉→髂内静脉→下腔静脉
E . 门静脉→脾静脉→奇静脉→上腔静脉