A teacher places 6 marbles in a bag. There are 1 blue marbles, 2 red marbles and 3 yellow marbles. A student draws one marble from the bag, does not replace it, then draws another marble from the bag. What is the probability that the first marble will be yellow and the second marble will be red?
A.1/5
B.1/6
C.4/5
D.3/20