Answer:
B - array; hash
Explanation:
Arrays store elements of the same data type in a list. Every element in the array is assigned a unique integer (starting at 0). You are able to access/process an element by using its assigned integer. Hashes are similar in the fact that they also store data. The difference is that each element is assigned an object type (instead of an integer), making it a collection of key pairs, as such you would typically not use this to process elements efficiently.
