Answer with Step-by-step explanation:
Volume of a prism = (Area of base) ×Height
Volume of a pyramid =

The pyramid has the same base as the prism.Hence, area of base will be same for both.Let it be a.
Height of pyramid is 3 times height of prism.
Let height of prism be h.
Height of pyramid=3h
Volume of a prism = ah
Volume of a pyramid =

= ah
Hence, Volume of pyramid/Volume of prism=1
Hence, correct option is:
b. volume of pyramid/volume of prism=1