Multiple choice technology programming languages

List Names = new List(); Names.Add("A"); Names.Add("B"); Names.Add("C"); var res = Names.Where(n => n == "D"); if (res == null) Console.WriteLine("res is null"); else Console.WriteLine("res is not null"); Console.Read(); What would be printed?

  1. res is null

  2. res is not null

  3. Run time error

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The Where() method returns an IEnumerable sequence, never null. Even when no elements match the predicate (n==D), it returns an empty enumerable, not null. The condition res==null is always false for LINQ query results, so res is not null prints. This is a common misconception about empty sequences.

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