is know to us all is that the old worker for life was hard in the past still works har

问题补充：

is know to us all is that the old worker, for life was hard in the past, still works hard in his seventies.

A. As; whom

B. What; whose

C. It; whose

D. What; whom

答案：

A. As; whom

B. What; whose

C. It; whose

(答案→)D. What; whom

解析：第一空填What，是由What 引导的名词性从句作主语。第二个空是定语从句，whom

指前面的先行词the old worker。故答案选D。