The base type of an array may be all of the following but:

A) string
B) boolean
C) long
D) all of these may be a base type of an array.

Base Type

The fundamental data type from which a complex data type can be derived, often used in the context of inheritance in object-oriented programming.

Array

An array is a data structure consisting of a collection of elements, each identified by at least one array index or key.