Correct option is B
The correct answer is (b).
Explanation
Fertilizers are chemical substances that supply specific nutrients required for plant growth, mainly nitrogen, phosphorus, and potassium. They do not add humus to the soil, and they are not carbonic salts. Hence, only statements {a} and {d} are correct.
Additional Information
• Option {a} is incorrect because fertilizers are not carbonic salts. • Option {c} is incorrect because fertilizers do not add humus to soil. • Option {d} is incorrect because fertilizers are not carbonic salts.