an important decision more on emotion than on reason, you will regret it sooner or later.
A. Based
B. Basing
C. Base
D. To base
网友回答
A. Based
(答案→)B. Basing
C. Base
D. To base
解析：考查分词做状语的用法。Base sth on sth把…放在…的基础之上。句子主语You与动词base构成主动关系，故使用现在分词的形式。句意：以情绪而不是原因决定，你迟早会为此后悔的。故B正确。