In .NET, which of the following is NOT a value type?

In .NET, which of the following is NOT a value type?

• double
• char
• int
• string

EXPLANATION

Main features of value types

A variable of a value type contains a value of the type. For example, a variable of the int type might contain the value 42. This differs from a variable of a reference type, which contains a reference to an instance of the type, also known as an object.
When you assign a new value to a variable of a value type, that value is copied. When you assign a new value to a variable of a reference type, the reference is copied, not the object itself.

Source

https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/value-types