Which of the following lists the six macronutrients?

The six macronutrients essential for plant growth are nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. These nutrients are required in relatively large quantities compared to micronutrients. They play vital roles in plant functions, such as energy transfer, structural development, and overall biochemical processes necessary for healthy growth.

Nitrogen is crucial for amino acids and proteins, phosphorus for energy transfer and root development, and potassium for water regulation and enzyme activation. Calcium contributes to cell wall structure and stability, magnesium is a central element in chlorophyll and vital for photosynthesis, and sulfur is important for certain amino acids and enzymes.

Other options mention either micronutrients or a combination that does not include the correct macronutrient list. For instance, elements like iron, manganese, and zinc are classified as micronutrients, which plants need in smaller amounts. Therefore, the correct identification of the six macronutrients is highlighted by option B, making it the appropriate choice for this question.