小型被审计单位通常没有正式的财务业绩衡量和评价程序，管理层往往依据某些关键指标，作为评价财务业绩和采取适当行动的基础，注册会计师应当了解( )。

A．预测、预算和差异分析

B．投资分析趋势

C．管理层使用的关键指标

D．同行业的业绩比较

下列事件过程的功能是：建立一个名为Datal的随机文件，存放角度值及这些角度的正弦函数值和余弦函数值，角度为1，2，3，…，90。请在空白处填入适当的内容，将程序补充完整( )。
Private Type Ang
K As Integer
Sinx As Single
Cosx As Single
End Type
Dim Ksc As Ang
Private Sub Form_Click()
Dim Y As Single
Dim i As Integer
Dim Ksc As Ang
Open ______
Y = 3.14159 / 180
For i = 1 To 90
Ksc. K = i
Ksc. Sinx = Sin(i * Y)
Ksc. Cosx = Cos(i * Y)
______
Next i
Close #2
End Sub

A) "..\Data1.txt" For Random As #1 Len = 10
Put #1, i, Ksc
B) "..\Data1.txt" For Random As #1 Len = 10
Put #1, Y, Kse
C) "..\Data1.txt" For Random As #1

Put #1, i, Ksc
D) "..\Data1.txt" For Random As #1

Put #1, Y, Ksc