Daniel has a blue, a red, a green, and a yellow tie. He also has a red and a green shirt. He chooses a random tie and shirt for work each day using a bag containing a blue marble, red marbles, a yellow marble and green marbles. He would select his tie using the first marble and his shirt using the second marble. Why would this model only work some of the time instead of every time when he chooses his clothing options?

1. He could choose two red marbles
2. He could choose two green marbles
3. He could choose a yellow marble and then a green marble
4. He could choose a red and then a yellow marble