Robin, Steven, and John are comparing tree diagrams for rolling double sixes on two six-sided number cubes (6, 6). Robin thinks the probability is 1/36 based on the tree diagram they created. Steven disagrees and argues that the probability of rolling double sixes is 1/6. John counts twelve outcomes and claims the probability is 1/12. Who correctly found the probability of rolling double sixes using the tree diagram?
A: Robin because there are 36 outcomes and only one is (6, 6).
B: Steven because there are 6 outcomes and only one is (6, 6).
C: Steven because there are 36 outcomes and six of them are (6, 6).
D: John because there are 6 outcomes for each and only one is (6, 6).