It is said in the book that Thomas Edison (1847—1931) the world-leading inventor for sixty years.
A. would be
B. has been
C. had been
D. was
网友回答
A. would be
B. has been
C. had been
(答案→)D. was
解析：根据括号内的1847—1931可知，此处应填过去时态；另外，由于没有另一个过去的时间或动作与之比较，故不能用过去完成时，即只能选D。