下列符号常量的声明中 ______ 是不合法的。A.Const a As Single =1.1B.Const d As Integer =“12”C

下列符号常量的声明中，______ 是不合法的。

A．Const a As Single =1.1

B．Const d As Integer =“12”

C．Const b As Double = Sin(1)

D．Const c As String = “OK”

请帮忙给出正确答案和分析，谢谢！