# Which one of the following must be true about any acceptable product code?

Leslie on July 3, 2019

why are we not looking at both scenarios when considering answers A and B but we do when looking at C, if looking at both scenarios then A and B would be correct as well

Ravi on July 22, 2019

@Imary,

Great question.

Using the rules of the game, we find that there are 6 possible game
boards for this game.

1 2 3 0 4
1 2 0 3 4
1 2 0 4 3

2 4 1 0 3
2 4 0 1 3
2 4 0 3 1

We're looking for something that must be true across all worlds.

(A) is invalidated by the last 3 worlds, so it doesn't have to be true.

(B) is invalidated by the last world, so it doesn't have to be true.

(C) is always true (2 is before 3 in every world), so it must be true
and is the correct answer choice.

(D) is only true in the first world and is false in all of the other
worlds, so it's out.

(E) is not true in the first two worlds, so it's out.

Does this make sense? Let us know if you have any other questions!