Which of the following is NOT a common abbreviation for medication dosages?

The indicated choice of 'D' is correct because 'cm' stands for centimeters, which is a unit of measurement for length and not typically used in the context of medication dosages. In contrast, 'mg' refers to milligrams and is a common unit for measuring the weight of medications; 'ml' refers to milliliters and is a standard unit for liquid volume in medication dosages; and 'gm' is an abbreviation for grams, also a common unit of weight used in pharmacology, though less frequently than milligrams for many medications. The focus of this question is on understanding the appropriate and relevant abbreviations that relate to medication dosages, highlighting 'cm' as the outlier.