问题补充：
They succeeded in killing pests which came from the foreign countries a lot of hard work.
A. according to
B. thanks to
C. in memory of
D. in addition of
答案：
A. according to
(答案→)B. thanks to
C. in memory of
D. in addition of
解析：词组辨析题。多亏了他们的努力从国外来的昆虫被成功扑杀。A. according to 按照 B. thanks to 多亏 C. in memory of 为纪念 D. in addition of 此外根据语境选B
