Final answer:
In the 1960s, Campbell's vegetable soup company used marbles to create the illusion of a vegetable-filled bowl in magazine advertisements.
Step-by-step explanation:
In the 1960s, Campbell's vegetable soup company filled a bowl with marbles and poured the soup over the top in magazine advertisements. They did this to create the illusion that the bowl was filled with vegetables, which would sink otherwise. This technique was used to make the soup appear more appealing in pictures.