My dictionary ________ . I have looked for it everywhere but still ______ it .

A．has lost ; do not find

B．is missing ; do not find

C．has lost ; have not found

D．is missing ; have not found

电影《英雄》中，刺客无名对秦王说，“剑”字有18种写法。秦王说，统一以后要只留一种。请问：秦统一后通行全国的标准文字是：

A．大篆
B．小篆
C．甲骨文
D．金文