Which trophic level is there the least energy available?   asecondary consumer  bprimary consumer  ctertiary consumer  dproducer

The trophic level with the least amount of energy available is the C. TROPHIC LEVEL

C- tertiary Consumer

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.