You are developing an application that includes a class named Order. The application will
store a collection of Order objects.
The collection must meet the following requirements:
Internally store a key and a value for each collection item.
Provide objects to iterators in ascending order based on the key.
Ensure that item are accessible by zero-based index or by key.
You need to use a collection type that meets the requirements.
Which collection type should you use?

A.
LinkedList

B.
Queue

C.
Array

D.
HashTable

E.
SortedList

Explanation:
http://msdn.microsoft.com/en-us/library/system.collections.sortedlist.aspx