A chemical bond between two atoms is:
A. The tunnel in an atom through which the another one can pass
B. The energy of the individual atoms
C. The link between them
D. A third connecting atom

Hint: Formation of chemical bonds can take place in various ways ,like if it is formed due to electrostatic force of attraction between ions an Ionic bond is formed while if mutual sharing of electrons takes place the bond formed is known as covalent bond.

Complete solution:
As we all know in our surroundings there are numerous amount of elements that exist in various forms
Some of their forms might be stable making them chemically inert while other might make them unstable such that they behave as a highly reactive element
Stability in chemistry is achieved through a stable electronic configuration like those of the Inert Gases like Xenon, Neon, Helium and Argon.
An element can achieve the desired electronic configuration that makes it stable through ways as follow
By transfer of electrons
By mutual sharing of electron
By accepting electrons
The method chosen by the element depends completely on its existing state
If it is a metal with less than four electrons in outer shell it does transfer of electrons to achieve stable state
A non-metal generally prefer mutual sharing of electrons and accepting electrons in order to gain stable electronic configuration
So whenever these process occur simultaneously between two atoms it leads to the formation of a chemical bond between them
A chemical bond thus can be defined as
“A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds. The bond may result from the electrostatic force of attraction between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bonds”.
This bond is the force of attraction between those two atoms at the same time it acts as a link between them such that they exist together.

Hence the most appropriate option for this question is ‘C’

Note: Bond formation is always accompanied with evolution of heat and hence is exothermic, while breaking of bond requires heat and thus falls under the category of endothermic.