Will you please inform us _______ of the extent of their reputat

Will you please inform us _______ of the extent of their reputation.
A、with confidence
B、in confidence
C、as confidential
D、of confidentially
【正确答案】：B
【题目解析】：in confidence 秘密地
句意：请将该公司的信誉可靠程度告知我方。