Which two statements are true for a two-dimensional array?

Question

Options

• AIt is implemented as an array of the specified element type.
• BUsing a row by column convention, each row of a two-dimensional array must be of the same size
• CAt declaration time, the number of elements of the array in each dimension must be specified
• DAll methods of the class Object may be invoked on the two-dimensional array.

• A
  88% (53)
• B
  8% (5)
• C
  3% (2)

Explanation

In Java, a two-dimensional array is fundamentally an array of arrays - meaning int[][] is literally an array whose elements are int[] objects, confirming A. Since arrays are objects in Java and all objects inherit from java.lang.Object, methods like equals(), hashCode(), and toString() are always available on any array, making D correct. B is wrong because Java supports jagged arrays - each row is an independently allocated array and can have a different length (e.g., arr[0] can have 3 elements while arr[1] has 5). C is wrong because dimensions are not required at declaration time; you can write int[][] arr; or new int[3][] and specify (or skip) inner dimensions later.

Memory tip: Think of a 2D array as a "folder of lists" - the folder is an object (so Object methods apply), and each list inside can be a different length (no forced uniform rows). Declaration just names the folder; you fill it in later.

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