Answer: Option (A) is the correct answer.
Step-by-step explanation:
Atomic number of carbon is 6. Hence, the electronic configuration of carbon is 2, 4.
This means that there are four valence electrons present in valence shell of the carbon atom. So, in order to complete its orbital and gain stability carbon will make its outermost four electrons available for sharing.
Thus, we can conclude that out of the given options because it has four electrons available for bonding is the best explanation for why carbon easily forms many bonds.