问题
选择题
Some blood types are quite common, others are regionally , and still others are rare everywhere.
A．distributed
B．contributed
C．obtained
D．Convinced
答案
答案：A
题目分析：考查动词辨析。句意：一些血型很常见，而有一些呈地区分布，但仍有少量血型很罕见。distribute分布；分配；contribute；贡献；有助于；obtain得到；获得；convince使信服；确信。根据句意可知A项正确。故选A。