You use Microsoft .NET Framework 4 to create a Windows Presentation Foundation (WPF) application. <br /> You write the following code fragment.<br /> <img src="https://nimg.ppkao.com/2018-07/yiyu/201807271446374677.jpg?sign=ee9a7656a061b66a62b8356b27509829&t=62d42fb5" /><br /> You need to implement the MyProject.AverageConverter class. <br /> What should you do?()
A、 Implement the IValueConverter interface.
B、 Implement the IMultiValueConverter interface.
C、 Inherit from the TypeConverter class.
D、 Apply the TypeConverterAttribute attribute.