单项选择题

A.内径约0.9cm,中性氧化铝5g,湿法装柱,30mL乙醇预洗
B.内径约0.3cm,酸性氧化铝5g,干法装柱,30mL乙醇预洗
C.内径约0.9mm,中性氧化铝5g,干法装柱,30mL水预洗
D.内径约0.2mm,硅胶5g,湿法装柱,30mL乙醇预洗
E.内径约0.9cm,硅藻土5g,湿法装柱,2mL甲醇洗、再0.5mL水洗