Answer:
Option B, by calculating water displacement
Step-by-step explanation:
As per the Archimedes Principle, the volume of the amount of water displaced by an object when it is placed in water is equal to volume of the object.
By this logic, Julio in this experiment is trying to measure the amount of displaced water . Once she gets the quantity of displaced water , she can easily deduce the volume of small pebble as volume of displaced water will be equal to the volume of small pebble.
Hence, Option B is correct