Which of the following is NOT considered a requirement of citizens?

The correct choice identifies that voting is not legally mandated as a requirement for citizens. While voting is an important civic duty and strongly encouraged in a democratic society, it is not an obligation enforced by law. Citizens have the freedom to choose whether to participate in elections, reflecting personal choice rather than a legal compulsion.

In contrast, paying taxes, obeying laws, and serving on juries are considered mandatory responsibilities of citizens. Taxation supports government functions and public services; adhering to laws is essential for maintaining societal order; and serving on juries ensures that the judicial system operates fairly and impartially by involving citizens in legal proceedings. Thus, while voting is a fundamental right and responsibility in promoting democracy, it does not fall under the category of legal obligations like the other options do.