Robby had 4 4/9 bags of pet food. All of the bags held the same amount of food when they were full. Of Robby's 4 4/9 bags of pet food, 2/5 were dog food. How many bags of dog food did Robby have?
A. 34/45
B. 1 3/5
C. 1 7/9
D. 4 2/45