That's the condition that is part of the original puzzle, and that I left off (intentionally, but often left off in error). This is called the Wason selection task https://en.m.wikipedia.org/wiki/Wason_selection_task
Larry's answer is correct given that precondition.
What is interesting about this logic puzzle is that done in the abstract with even and odd numbers and two different colors, it can be pretty hard. But a real life application is trivial:
You want to determine if a law preventing persons under age 18 from drinking alcohol beverages is being complied with. You walk into a room and see two individuals who look to be in their late teens, one drinking a beer and one drinking a Coke. Two more people are drinking from opaque glasses, so you can't immediately tell what they are drinking. One of these individuals is clearly a young teen and the other is in his 40's. No one would have any problem determining which ids and which beverages to check. While no one will feel the need to see if the 40-yr-old is drinking beer, it is surprising how many people feel the need to check what is on the other side of the blue card.