The right answer is C
This process is called anaerobic respiration. It doesn't need dioxygen to occur (it can happen with or without O2).
Anaerobic respiration is a mechanism in which electrons pass through a chain of transporters whose final acceptor is a mineral substance other than oxygen, unlike aerobic respiration where the final acceptor is dioxygen. The final acceptor may be the nitrate ion (as in the case of Pseudomonas), carbon dioxyde or the sulfate ion.
Some bacteria (Pseudomonas) are able, anaerobically, to reduce nitrates to nitrites and then, depending on the case, to dinitrogen (with the enzyme Nitrate reductase A).
NO3- ==> NO2- ==> N2.
<span>With the do until structure, the statements in the loop are repeated as long as a certain condition is false. The do until structure is used in order to execute a block of statements in an unspecified number of times until a condition becomes true.</span>
Sex (sexual reproduction), is the act of reproducing. Each species of animal and plant do it in a different way, and some just choose to do it by themselves. And yes, according to a good percent of the population, sex does feel good.