Luke has red marbles and blue marbles in a bag. If he chooses a marble at random, the probability that he will choose a blue marble is \frac25. Luke adds 5 blue marbles to the bag and removes 5 red marbles. If he chooses a marble at random, the probability that he will choose a blue marble is now \frac35. How many marbles are in the bag?
Answer Choices
A. 20
B. 10
C. 45
D. 50
E. 25