What Will Be the Value of DblSum After the Button

Multiple Choice

What will be the value of dblSum after the button btnAdd is clicked, assuming that 25 is entered by the user into txtNum1, and 35 is entered into txtNum2?
Private Sub btnAdd_Click(ByVal sender As System.Object, _
ByVal e As System.EventArgs) Handles btnAdd.Click

Dim dblNum1, dblNum2, dblSum As Double
DblNum1 = CDbl(txtNum1.Text)
DblNum2 = CDbl(txtNum2.Text)
DblSum = Sum(dblNum1, dblNum2)
LblSum.Text = dblSum.ToString()

End Sub

Function Sum(ByVal dblNum1 As Double, ByVal dblNum2 As Double) as Double
Return dblNum1 + dblNum2
End Function

A) 60
B) 50
C) 0
D) 70