If it’s something you really don’t know, you can say something along these lines, “Unfortunately, I haven’t had the opportunity to work with C#; however, I have so much experience in VB.NET that I feel like I can transition easily.”
If it’s something you really don’t know, you can say something along these lines, “Unfortunately, I haven’t had the opportunity to work with C#; however, I have so much experience in VB.NET that I feel like I can transition easily.”