A bag contains 6 red marbles, 4 blue marbles, and 2 green marbles. If one marble is drawn at random, what is the probability that it is a blue marble?

✓ Correct Answer: Option C

Total number of marbles is 6 + 4 + 2 = 12. There are 4 blue marbles. The probability of drawing a blue marble is 4/12, which simplifies to 1/3.