The answer is "Decomposers directly convert ammonium into nitrogen gas".
Living organisms such as plants and animals contains nitrogen in the form of the amino acids and proteins. When they die, the nitrogen in the form of ammonium is decomposed by microorganisms. It is then converted into nitrites and then to nitrates by nitrifying bacteria. The denitrifying bacteria then converts nitrates into nitrogen.
Answer:
the answer would be C, secondary consumer since the zebra is the primary consumer and the plant is the producer
C the presence of harmful substances in food