AIIMS 2019 Biology Micronutrients MCQ Question

Option A is correct because it lists elements that are classified as micronutrients, which are essential in small quantities for plant growth and development. These include manganese (Mn), zinc (Zn), iron (Fe), boron (B), chlorine (Cl), and nickel (Ni), all of which play critical roles in various physiological processes. In contrast, options B and C contain macronutrients like carbon (C), sulfur (S), oxygen (O), nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), and phosphorus (P), which are required in larger amounts. Option D also includes carbon (C) and hydrogen (H), which are not micronutrients, and while it includes some micronutrients like iron (Fe) and manganese (Mn), it does not exclusively represent micronutrients.