某电阻两端的电压为20伏时，通过它的电流为2安，它的电阻是______欧；如果它两端的电压减小到15伏时，通过它的电流是______安，这时它的电阻是______欧；如果通过它的电流是1安，它两端的电压为______伏，这时它的电阻是______欧．

A production process has been defined as part of an industrial equipment manufacturing project. The process is intended to produce steel bolts with a length of 20cm. The control limits are 19.955cm and 20.045cm. The measurements made at the end of the process yielded the following results: 20.033cm, 19.982cm, 19.995cm, 20.006cm, 19.970cm, 19.968cm, 19.963cm, 19.958cm, 19.962cm, 19.979cm, 19.959cm. What should be done ？（）

A．The process is tinder contr01. It should not be adjusted.

B．A special cause should be investigated, the process should be adjusted.

C．The control limits should be adjusted.

D．The measuring equipment should be recalibrated.