________ X-rays were first discovered by ________ German scientist, Wilhelm K．Rontgen, in 1895, almo

________ X-rays were first discovered by ________ German scientist, Wilhelm K．Rontgen, in 1895, almost by ________ accident．

A./, a,/

B.The, a, an

C.The, the,/

D./, the, the

答案及解析： A