To find the volume of the rectangular prism made up of 4 cubes that are each 15 inches on each side, we first calculate the volume of one cube.
The volume \( V \) of a cube is given by the formula: \[ V = \text{side}^3 \] For one cube with a side length of 15 inches: \[ V = 15^3 = 15 \times 15 \times 15 = 3375 \text{ cubic inches} \]
Since there are 4 such cubes, the total volume \( V_{total} \) will be: \[ V_{total} = 4 \times 3375 = 13500 \text{ cubic inches} \]
Now let's look at the answer choices. The volume of the rectangular prism is 13500 cubic inches, and none of the options match this result.
But given that the factors were at play that makes it seem that 13500 cubic inches does not match any other choices—and they seem to indicate fractional answers—it's important to double-check any provided answer options in case of mismatches or miscalculations.
Since there is no correct response from the options, taking the primary volume as an integer representation is our best route unless there's an error or miscommunication in the question context regarding reducing terms or alternate values.
However, if you are specifically looking for which response to choose based on closest match to proper volume calculation, it can only be understood through additional observation. Based on available numbers:
None of the provided options align with the standard calculation based on a straightforward cube multiplication of the respective values.
To summarize, the calculated volume is 13500 cubic inches which is different from options provided, hence I recommend seeking further clarification on the question context from source materials or verifying numerical options offered or alternate resolutions.