Final answer:
The size declarator must be a non-negative integer which is greater than zero.
Step-by-step explanation:
An array is defined as the collection of similar type of data items stored at contiguous memory locations. Arrays are the derived data type in C programming language which can store the primitive type of data such as int, char, double, float, etc.
The size declarator in programming must be a non-negative integer and must be greater than zero, as it determines the number of elements in an array. In computer programming, especially when defining arrays, the size declarator indicates the number of elements that the array will hold.
It is imperative that this size is clearly defined and that it is an integer because you cannot have a fraction of an element.
Moreover, it needs to be greater than zero, as having an array with a size of zero or a negative size would not make logical or practical sense in most programming contexts.