Explanation

Plants require macronutrients in large quantities. Option A lists primary macronutrients (N, P, K) and Option B lists secondary macronutrients (S, Mg, Ca). Iron (Fe) is a micronutrient, but in many general agricultural contexts, the combination of NPK and S/Mg/Ca represents the major mineral nutrients needed in larger amounts compared to trace elements. Therefore, both groups are essential for normal development.