Every year, the coal workers their lungs X-rayed to ensure their health.
A. are having
B. have had
Chave
D. had had
网友回答
A. are having
B. have had
(答案→)C. have
D. had had
解析：考查时态题。根据时间状语every few years,可判断本句应为一般现在时，have lungs X-rayed意思是“请人检查肺”。因此答案选C。