In 1927 Benjamin Franklin founded one of the first adult-education organizations, the Junto.
A. has been called
B. to call
C. a group called
D. which group called
网友回答
A. has been called
B. to call
(答案→)C. a group called
D. which group called
解析：
根据句子意思，a group called…用作同位语，对前边起补充说明作用，其中called the Junto是过去分词短语用作定语。