why do we prefer ? to ?? operator in c#?

Question

I recently found that we can use ?? operator to check nulls. Please check the below code samples:

   var res = data ?? new data();

This is

Answer 1

One reason I can think of is that this operator was introduced in .NET 2.0 so the code for .NET 1.1 cannot have it.

I agree with you, we should be using this more often.

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