I roll a loaded 6-sided die.

Define the following marginal probabilities: P({1}) = 0, P({2}) = 1/3, P({3}) = 1/6, P({4}) = 1/6, P({5}) = 1/3, P({6}) = 0.

Let event Q = "Roll a multiple of 3." What is the probability of event Q?

a.1/3

b.1/6

c.5/6

d.1/2