托业考试

试题来源：托业-4
【单选题】 Ms. Ravi has already conducted market research ______two new products.
A．(A) around
B．(B) from
C．(C) on
D．(D) near

参考答案：C
网考网解析：
On is the preposition used with conduct research. Choice (A) means concerning. Cho... 查看试题解析出处>>