Answer:
Negative feedback.
Explanation:
The production of erythropoietin by the liver and kidneys is a negative feedback because with the production of erythropoietin, our body tends to move to become more stable state. The erythropoietin is produced by the liver and kidneys to increase the production of red blood cells if the quantity of red blood cells are lower than the normal range. If the number of red blood cells are decreases the oxygen level in our body is low that leads to unstable condition of the body but when the concentration of red blood cells increases, the body move towards stability.
<span>The correct option is A. In nuclear fusion, two deuterium nuclei are fused together in the presence of high temperature and pressure to produce HELIUM NUCLEUS, neutron and energy. Very high quantity of energy is liberated during the process. Deuterium is a stable form of hydrogen and is found in water. </span>
