<span>Enzymes lower the activation rate of a reaction, thus lowering the energy needed to start a reaction.</span>
The correct answer is Eutrophication.
When a body of water become enriched with nutrients and minerals and induces growth of algae and plants is referred to as eutrophication.
The process of eutrophication can result to water body depletion.
When there is increase in nutrient levels there is increase in phytoplankton in the water body.
Discharge of nitrates which contain sewage, fertilizer, and detergents in aquatic system may induce the eutrophication.
The given blank can be filled with enzymatic molecules.
Enzymes refer to biological molecules or proteins, which function as catalysts and assist the composite reactions to take place everywhere in life. The enzymes generally end with the suffix - ase. For example, proteases, which functions to dissociate the peptide bonds between the amino acids.
Enzymes are big molecules, which accelerate the rate of chemical reactions within the cells, and like all other kinds of proteins, they comprise lengthy chains of amino acids.
C.
Biotic mean alive, so we can cut off the first 2 easily. Aquatic birds eat frogs, so that one is safe for now. A decrease in something parasitic usually helps the population, so D is out too. The only one left is C.