To solve this question, the user needs to have knowledge of arrays and computer memory.

The memory address of the first element of an array is called the base address. This is because the base address is the starting point or foundation of the array in memory. It is the address at which the first element of the array is stored.

Therefore, the correct answer is:

The Answer is: D. base address.

Option A is incorrect because floor address is not a term used to refer to the memory address of the first element of an array.

Option B is incorrect because foundation address is not a term used to refer to the memory address of the first element of an array.

Option C is incorrect because first address is not a term used to refer to the memory address of the first element of an array.