Chemical pollution will bring about a threat to agriculture and food chain, and to human health.
A. frequently
B. significantly
C. steadily
D. consequently
网友回答
A. frequently
B. significantly
C. steadily
(答案→)D. consequently
解析：副词辨析。A频繁地；N重要地；C稳定地；D所以，因而，因此；结合句意可知D正确。句意：化学污染给农业和食物链产生很大的威胁，因而对人类的健康也会有很大的威胁。