Final answer:
The volume of a rectangular prism is calculated by multiplying its length, width, and height together, which corresponds to option D) length x width x height.
Step-by-step explanation:
The volume of a rectangular prism is calculated by multiplying its length, width, and height. When calculating the volume, these dimensions are multiplied in sequence, which can be represented as length x width x height. Although the multiplication of real numbers is associative, meaning that it doesn't matter in which order you multiply them ((length x width) x height is the same as length x (width x height)), the standard formula designated for this is simply the product of these three measurements. Therefore, the correct answer is D) length x width x height, which represents the most straightforward expression for the volume of a rectangular prism.