If no loss or gain of electrons occur by mixing of two atoms, we say that they may be attached to each other due to
A proton attraction
B neutron attraction
C sharing of electrons
D opposite charges
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The correct option is option C

Explanation:

Loss or gain of electron(s) occurs in a type of attraction known as electrovalent or ionic attraction. In this type, there is transfer (or loss) of electron(s) from a metal atom to become positively charged while a nonmetal accepts (or gains) this electron to become negatively charged.

When this does not happen, two metal atoms can become attached by sharing the same electrons through a form of attraction known as covalent bonding. Here, the two atoms share electrons (known as shared pair) together to achieve there octet configuration on the outermost shell.  

where are the choice options?

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