Answer: A) The volume of the pyramid is 1/3 the volume of the rectangular prism.
Step-by-step explanation:
Let's say we had a rectangular block that has a volume of 90 cubic meters. If we wanted a pyramid that had the same base as the block, then the pyramid would have 1/3 of that 90 m^3 volume. The pyramidal volume would be (1/3)*90 = 30 m^3.
Put another way: we can fit 3 pyramids into one rectangular block.