Covalent bonds are formed by the sharing of electrons between two atoms so that both can achieve a completely filled _____________ shell.

Correct option is D

Ans: (D) Outermost

Explanation:
Covalent bonds are formed by the sharing of electrons between two atoms so that both can achieve a completely filled outermost shell.

Information Booster:

• Covalent Bonds: Formed when atoms share electrons to complete their outermost electron shell, which is also known as the valence shell.
• Molecules: Common molecules formed by covalent bonding include H₂O (water), O₂ (oxygen), and CO₂ (carbon dioxide).
• Octet Rule: Atoms follow the octet rule, aiming for 8 electrons in their outermost shell to achieve a stable electron configuration.
• Electron Sharing: Electrons are shared in such a way that both atoms involved in the bond can achieve a full outermost shell, resulting in a stable molecular structure.