He tried to deal with the increasing burden of his work, but he finally ______ and had to take a complete rest.

[      ]

A. broke off

B. broke away

C. broke out

D broke down

模具加工自动编程时应合理设置公差，以平衡加工精度和计算机计算时间，精加工光面时，公差一般设为（）。

A.0.02mm

B.0.01mm

C.0.005mm

D.0.001mm