Every possible test was carried ________ to decide the nature of

Every possible test was carried ________ to decide the nature of her illness.
A、on
B、of
C、out
D、through
【正确答案】：C
【题目解析】：carry on是继续发展,坚持的意思,carry of没有这个词,carry through是进行的意思, carry out 是实现的意思。原句的意思是：为了确定她的病情，进行了各种可能的试验。因此选C