Answer:
a. nitrogen is the correct answer.
Step-by-step explanation:
- Nitrogen is a macronutrient because nitrogen present in the plant in large quantities.
- Macronutrients are the nutrients which are needed in large amount for the proper growth and development,as they are required in large amounts they are called macronutrients.
- Macronutrients are the most essential elements for plants and required so that body functions properly.
- Macronutrients comprise carbon, nitrogen, sulfur, oxygen, potassium, hydrogen, calcium, phosphorus and magnesium.