If the scale factor of the small pool to the large pool is equal to 0.12, the ratio of their volumes should be equal to 0.12^3 or equal to 1.728 x 10^-3. We multiply this value to the given volume of the large pool to get the volume of the small pool.
volume of small pool = (1.728 x 10^-3)(15,000 m^3)
volume of small pool = 25.92 m^3
Hence, the answer is the first choice.