Correct version of C# and .NET framework

What will be the Version of C# if you are using .NET Version 3.5??

First it's sad to see these kind of questions in senior interviews as they do not test developers capability.

There is no direct mapping of language and framework versions. In other words if you have .NET 3.5 does not mean that you have C# 3.5. For .NET 3.5 we its C# 3.0. Mostly languages do not have minor versions. In other words you will not see C# 3.5 , C# 4.5 and so on. It mostly major versions. Below is the list of framework and C# versions.

C# 1.0	.NET 1.0
C# 1.2	.NET 1.1
C# 2.0	.NET 2.0
C# 3.0	.NET 3.5
C# 4.0	.NET 4
C# 5.0	.NET 4.5
C# 6.0	.NET 4.6