What could be the maximum size of an array in C programming?

Its depends on your on your system properties if you have a 32 bit operating system, the size of an array is about 2^32 which is almost few hundred GigaByte memory if have a higher Ram than the array it can show you the results else it show you run time error.The size of an array completely depends on your system properties.

The minimum limit was raised in the 1999 update to the C standard to be at least 65,535 bytes.
In simple words, it is not possible to say in advance how large an array can be created. It is depend on things like the amount of physical memory installed on the computer and the amount of virtual memory provided by the OS.
On some platforms you can create larger arrays if they are static or dynamic allocation.