Which of the following is least likely an indicator of impairment（）

A. Large cost overruns.

B. Negative changes in the business climate.

C. The market value of an asset appreciates unexpectedly.

已知地形图上A点位于94m和95m两条等高线之间，通过B点作垂直于等高线的直线mn，交94m等高线于m点，交95m等高线于n点，在图上量取mn=6cm，mb等于1.5cm，等高距为1m，地形图比例尺为1：500，则B点的高程为（）。

A.94.25

B.94.75

C.94.5

D.无法确定