C# Programming - MCQ Practice Questions

Which namespace in C# contains the collections like List<T>, Dictionary<K,V>, and Queue<T>?

What is the main difference between ArrayList and List<T> in C#?

Which collection allows duplicate keys in C#?

What does the Count property of a collection return in C#?

Which collection in C# implements LIFO (Last In First Out) principle?

What will be the output of the following code? List<int> nums = new List<int> {1, 2, 3}; nums.Add(4); Console.WriteLine(nums.Count);

Which collection in C# maintains insertion order and allows duplicate elements?

Which collection throws an exception when you try to dequeue from an empty Queue<T>?

What is the time complexity of accessing an element by index in List<T>?

Which method in Stack<T> returns the top element without removing it?

Which IEnumerable method should be used to filter elements based on a condition and maintain type safety?

In a HashSet<T>, what happens when you try to add a duplicate element?

Which LINQ method should you use to transform each element of a collection into a new form?

Which method in Queue<T> allows you to examine the front element without removing it?

Which collection type uses a hash table internally and provides O(1) average lookup?

What does the Add() method return when adding a duplicate element to a HashSet<T>?

What is the space complexity of a HashSet<T> with n elements?

What does the Peek() method do in a Stack<T>?