Final answer:
Iron is not a macronutrient. Macronutrients are nutrients that our body needs in large amounts and provide energy. So the correct answer is Option A.
Step-by-step explanation:
The correct answer is A. Iron. Iron is not a macronutrient. Macronutrients are nutrients that our body needs in large amounts and provide energy. They include carbohydrates, proteins, and fats. Iron, on the other hand, is a micronutrient that our body needs in smaller amounts for functions like transporting oxygen and making red blood cells.