Since no one really knows what effects the GM food might have us humans, many countries think that they should be cautious this new technology.
A. about; with
B. on; to
C. in; to
D. on; with
网友回答
A. about; with
B. on; to
C. in; to
(答案→)D. on; with
解析：
根据句意：因为没有人真正知道转基因食物可能对我们人类有什么影响，许多的国家认为他们呢应该对新技术抱以谨慎的态度。
have effects on sth 对…有影响
be cautious with sth 对…谨慎小心的
be cautious to do sth 对做…谨慎小心的。故选D