The answer is D, species!
Hope this helps!
Answer:
A chemical reaction in which an uncombined element replaces an element that is part of a compound is called a simple substitution reaction or simple displacement reaction.
Explanation:
A simple substitution reaction or simple displacement reaction, called single-displacement reaction, is a reaction in which an element of a compound is substituted by another element involved in the reaction. The starting materials are always pure elements and an aqueous compound. And a new pure aqueous compound and a different pure element are generated as products. The general form of a simple substitution reaction is:
AB + C → A +BC
where C and A are pure elements; C replaces A within compound AB to form a new co, placed CB and elementary A.
So, in a Single replacement reaction an uncombined element replaces an element.
<u><em>A chemical reaction in which an uncombined element replaces an element that is part of a compound is called a simple substitution reaction or simple displacement reaction.</em></u>
<span>This example represents the challenge of survival of the fittest. In this situation, the trees have a distinct advantage due to their above average height. This puts them in the best position to gain the resources that they need to survive, most notably, the sun. The smaller plants, however, do not have this advantage, and lose out to the trees.</span>
They depend on nitrogen-fixing bacteria, which convert atmospheric nitrogen into a usable form.