B.

According to the Environmental Working Group which advises the USDA, avocados top the “Clean Fifteen” list as the #1 fruit/vegetable least likely to carry dangerous chemical residues from pesticides. Carrots are on the “Clean” list too, coming in at #15. In the opposite direction, topping the “Dirty Dozen” list of fruits/vegetables most likely to have such residues are strawberries (#1) and spinach (#2). So wash them well!