Question

Which of the following cannot be provided to the soil by a chemical fertilizer?
A. nitrogen
B. humus
C. potassium
D. phosphorus

Answer 1

Answer:

humus cannot be provided by a chemical fertilizers

Explanation:

humus is a naturally occurring substance and so cannot be provided by chemicals

Answer 2

B. humus

Explanation:

Fertilizers are chemical substances which are rich in a particular nutrient. Some examples of fertilizers are urea, potash, NPK (nitrogen, phosphorus, potassium), etc. Use of fertilizers, however, are not preferred by organic farmers. Organic farmers use crop rotation and use of organic manures to enrich the soil with nutrients. Excessive use of fertilizers can makes the soil less fertile and also causes water pollution.

Humus is found in manure, not in fertilizer. So option B is the answer.