These materials are the most important records we keep ________ those men's places,time and mea

These materials are the most important records we keep ________ those men's places,time and means of gambling．

A.for

B.on

C.up

D.of

答案及解析： D

解析：

考查介词。此题只要看出短语结构keep record of，便可选出答案。