On a coordinate plane, a straight line with a positive slope begins at point (0, 50) and ends at point (5.5, 600).
Which scenario is most likely the one shown on the graph?

the total amount of money in the cash register, y, containing $50 in change and small bills and x $100 bills
the total number of puzzle pieces, y, in a brand new 50-piece puzzle, and x brand-new 100-piece puzzles
the total weight of the barbell, y, where the bar weighs 50 pounds and x 100-pound weights are added to it
the total number of calories, y, in a salad with vegetables containing 50 calories topped with x ounces of salad dressing at 100 calories per ounc