To answer this question, you need to understand the characteristics and performance considerations of different classes in .NET for key-based item retrieval.
Option A) OrderedDictionary class - This class maintains the insertion order of its elements. While it allows key-based retrieval, it is not optimized for performance in terms of large collections. The time complexity for key-based retrieval is O(n) because it searches through the collection linearly.
Option B) ListDictionary class - This class is optimized for small collections. It uses a simple list-based approach for storing key-value pairs. While it allows key-based retrieval, it is not efficient for large collections. The time complexity for key-based retrieval is O(n) because it searches through the collection linearly.
Option C) HybridDictionary class - This class is optimized for both small and large collections. It internally uses different data structures based on the size of the collection. For small collections, it uses a ListDictionary, and for large collections, it switches to a Hashtable. The time complexity for key-based retrieval is O(1) for large collections and O(n) for small collections.
Option D) Hashtable class - This class is optimized for key-based retrieval in large collections. It uses a hash table data structure, which provides constant-time (O(1)) performance for key-based retrieval. It is efficient for both small and large collections.
The correct answer is Option C) HybridDictionary class. This class is optimized for key-based item retrieval for both small and large collections. It internally uses different data structures based on the collection size, providing efficient retrieval performance.