Denitrification may be distinguished as

ANS:C - both (a) and (b)

When an inorganic compounds (nitrate, sulfate, carbon dioxide) is reduced for use as a nutrient source, its is said to be assimilated and the reduction process is called assimilative metabolism.

The use of Nitrate, sulfate or CO2 as electron acceptors for energy metabolism in an anaerobic respiration is called dissimilative metabolism.