Charlene went to the grocery store to pick up some items for her party. She bought 3 times as many bags of potato chips as bags of pretzels. She bought a total of 18 bags of potato chips. Let brepresent the number of bags of pretzels Charlene bought. Which of the following represents an equality between two different ways to express the total number of bags of potato chips she bought? A. 3 = 18 B. 3b + b = 18 C. b +3 = 18 D. 3b = 18​