4 boxes each containing balls are placed as follows. that box 1 contains 25 blue, 15 black and 20 red balls, box 4 contains 35 yellow, 10 red and 40 black balls, box 2 contains only 50 blue balls and box 3 contains 25 green, 15 white, 10 yellow and There are 5 blue balls - What is the difference between the total number of red and blue balls -

• A. 15
• B. 30
• C. 45
• D. 50