Some people hold the view that the new machine is advanced while others are still skeptic

问题补充：

Some people hold the view that the new machine is advanced, while others are still skeptical whether it is of practical use.

A. with

B. about

C. for

D. on

答案：

A. with

(答案→)B. about

C. for

D. on

解析：固定搭配be skeptical about sth，意思是对……疑惑，故选B。