Which property of $C$ best explains its ability to form large and complex molecules?

• A. $C$ has a high electronegativity, making it highly reactive with metals.
• B. $C$ can form $4$ covalent bonds, allowing it to create diverse and stable structures.
• C. $C$ can only form double bonds, limiting its structural diversity.
• D. $C$ atoms are always found in ionic compounds, which leads to complex structures.

Answer: (B)

Verified step by step guidance

1. Identify the key property of carbon (C) that influences its bonding behavior. Carbon has four valence electrons, which allows it to form up to four covalent bonds with other atoms.
2. Understand that the ability to form four covalent bonds enables carbon to create a wide variety of stable and complex molecular structures, including chains, branches, and rings.
3. Recognize that carbon's tetravalency (forming four bonds) is fundamental to the diversity of organic compounds, as it can bond with many different elements and itself in multiple ways.
4. Note that while carbon can form double and triple bonds, it is not limited to double bonds; this flexibility further increases the complexity of molecules it can form.
5. Conclude that the property of carbon forming four covalent bonds best explains its ability to form large and complex molecules, rather than its electronegativity or ionic bonding tendencies.