My answer will be C. Law of Original lateral continuity. :)
The question is incomplete, the complete question is:
Write the net ionic equation for the below chemical reaction:
(c): 
<u>Answer:</u> The net ionic equation is 
<u>Explanation:</u>
Net ionic equation is defined as the equations in which spectator ions are not included.
Spectator ions are the ones that are present equally on the reactant and product sides. They do not participate in the reaction.
(c):
The balanced molecular equation is:

The complete ionic equation follows:

As ammonium and chloride ions are present on both sides of the reaction. Thus, they are considered spectator ions.
The net ionic equation follows:

An atom is most stable when it has eight electrons in its outermost energy level.
Answer:
B
Explanation:
Economic principles has nothing to do with biome determination.
Answer: C)Anion, it would gain 2 electrons to satisfy the octet rule.
Explanation:
Electronic configuration represents the total number of electrons that a neutral element contains. We add all the superscripts to know the number of electrons in an atom.
The electrons are filled according to Afbau's rule in order of increasing energies and thus the electronic configuration of oxygen with 8 electrons is

The cation is formed by loss of electrons and anions are formed by gain of electrons.
In order to complete its octet and get stable, it gains 2 electrons and thus would form an anion.
