The development of industry has been gradual process throughout human existence from sto

问题补充：

The development of industry has been gradual process throughout human existence, from stone tools to modern technology.

A. /, the

B. the, a

C. a, /

D. a, a

答案：

A. /, the

B. the, a

(答案→)C. a, /

D. a, a

解析：考察冠词。第一空是泛指工业的发展是一个逐渐发展的过程，第二空的human existence是一个抽象的意义，故使用零冠词。故C正确。