It is obligatory for a common citizen to follow the rules.

optional
superfluous
necessary
advisable

The correct answer is C. necessary.

A rule is a regulation or directive that must be obeyed. It is obligatory for a common citizen to follow the rules because they are in place to protect the safety and well-being of everyone. Rules can also help to ensure order and fairness in society.

Option A, optional, is incorrect because it is not optional for a common citizen to follow the rules. Rules are in place for a reason and must be obeyed.

Option B, superfluous, is incorrect because rules are not

superfluous. They are necessary for the safety and well-being of everyone.

Option D, advisable, is incorrect because it is not advisable for a common citizen to follow the rules. It is obligatory.