Lists are one of the most useful data structures in applications of computer science. Anytime we need a collection of data, lists are often our first choice. Lists are an example of an abstract data type or (ADT). Which of the following statements best describes the meaning of this term?

A. When you are iterating through a list, you cannot see what's happening to the elements within unless you use lots of DISPLAY statements.

B. Lists can hold a variety of data types, including collections of heterogeneous data, and are therefore a useful abstraction.

C. Lists have useful procedures like APPEND REMOVE and INSERT associated with them. The INSERT procedure, for example, uses several steps to accomplish its job. We don't have to understand how these steps work in order to simply use the INSERT procedure.

D. Lists are organized by index, starting at 1. This makes them abstract compared to other data types like numbers which have no indices.