问题详情

The author implies that all the following statements about duplicate artifacts are true EXCEPT______.
A．a market for such artifacts already exists
B．such artifacts seldom have scientific value
C．museums are well supplied with examples of such artifacts
D．such artifacts frequently exceed in quality those already catalogued in museum collections此题为多项选择题。请帮忙给出正确答案和分析，谢谢！