Programming in C# — Question 81

You plan to create a list of customers named customers. Each customer will have a name and a key. The name and key will be strings.
You will use the following code to retrieve customers from the list. customers[aKey].toString();
You need to identify which class must be used to declare the customers list. The solution must ensure that each key is unique.
Which class should you identify?

Answer options

• A. ArrayList
• B. Dictionary
• C. List
• D. Array

Correct answer: B

Explanation

The correct answer is B, Dictionary, as it is designed to store key-value pairs where each key is unique. An ArrayList (A), List (C), and Array (D) do not enforce uniqueness of keys, which is essential for this scenario.