Answering this question shows you have the basic knowledge and skills required to fulfill the needs of the position. The right candidate should be a knowledgeable programmer who is comfortable coding within the .NET Framework. In addition to telling what languages the framework supports, you can also provide your experience programming within those languages.
Example: “The .NET Framework supports more than 60 languages. This includes both Microsoft and non-Microsoft languages. The most common languages are VB.NET, Cobol, Perl, C#, C++ and F# languages.
I began my programming career by learning C#. It’s provided an important foundation for my professional development as a programmer. When I got my C# programming certificate, I was promoted to a full-time developer at National Telecom Ltd. In that role, I also learned F# and Cobol. This makes me very familiar with these common languages applied to the .NET Framework.”