A Level Computer Science OCR Practice Exam

What characterizes a two-dimensional array?

1. A single index is used for searching

2. It consists of rows and columns

3. It can only hold integers

4. It cannot be indexed

The correct answer is: It consists of rows and columns

A two-dimensional array is characterized by its structure, which consists of rows and columns, forming a grid-like organization for storing data. This structure allows for the representation of more complex data types, such as matrices or tables, where each element can be accessed by specifying two indices: one for the row and one for the column. This definition is intrinsic to how data is organized in a two-dimensional array, enabling users to perform operations that involve multiple dimensions, such as matrix multiplication or storing data in a structured format. Each position in the array can hold a value, be it a number, character, or even an object, depending on the programming language and the array's intended use. In contrast, other options suggest misconceptions about two-dimensional arrays. For instance, suggesting that a single index is used for searching ignores the essence of a two-dimensional structure, which requires two indices for access. The idea that a two-dimensional array can only hold integers is incorrect, as arrays can store various data types as mentioned earlier, and stating it cannot be indexed ignores the fundamental characteristic of arrays, which allows each element to be located via indexing.