Which two are valid declarations of a two-dimensional array?

A is a valid declaration where the [][] notation specifies a two-dimensional array type directly after the primitive type int. This declares array2D as a reference to a 2D integer array without initializing it.

B is incorrect because array sizes (e.g., [2][2]) cannot be specified during the declaration of the array reference; they are provided during initialization using new.

C is incorrect because int array2D[] declares a one-dimensional array of integers, not a two-dimensional one.

D is also a valid declaration where [] follows int to indicate an array of integers, and then [] follows array2D to indicate that array2D is an array of integer arrays, effectively a two-dimensional array. This is syntactically sugar for int[][] array2D;.

E is incorrect because int[][] array2D[] attempts to declare a three-dimensional array, as the final [] adds a third dimension to the int[][] type.