Which one of the following nutrients is not available in fertilizers?
(a) Nitrogen
(b) Phosphorus
(c) Iron
(d) Potassium
Answer: C
Fertilizers are the chemical substances which provide nutrients to a plant, which leads to an increase in the growth and yield of a plant or crop. They provide Potassium, Nitrogen and Phosphorus to the plant. The use of these chemical substances(fertilizers) should be kept under prescribed doses as they can lead to water pollution and soil destruction if not used properly.
Hence, the correct answer is C.