If there are 5 people, they get 3 cans.
We want to give the same amount of soup to everyone, so if there are twice as many people, we're going to need twice as much soup.
(10 people, 6 cans)
Now say we had 20 people. (4 times as many)
We'd use 4 times as many cans soup, which would be 3×4 = 12 cans.
So it seems tht both B and D are correct.
