A nurse is caring for an 18-month-old infant who is 12 hr postoperative following a myringotomy. Which of the following pain rating scales should the nurse use?

A. Color tool: The color tool is typically used with older children who can understand color associations with pain levels. It is not as appropriate for an 18-month-old infant, who may not have the cognitive ability to understand this tool. B. Numeric scale: The numeric scale requires the ability to understand numbers and associate them with pain levels, which is generally used for children aged 8 or older. An 18-month-old infant would not be able to use a numeric scale. C. Poker Chip Tool: The Poker Chip Tool is used for children aged 3 and older who can understand the concept of "a few" versus "a lot" of chips. An 18-month-old would likely be unable to comprehend this tool. D. FLACC scale: The FLACC (Face, Legs, Activity, Cry, Consolability) scale is specifically designed for infants and non-verbal children. It assesses pain based on observable behaviors, making it the most appropriate tool for assessing pain in an 18-month-old infant.