Option 1: Bankrupt individuals are not prohibited from being registered as voters based solely on their bankruptcy status. However, the eligibility criteria for voter registration may vary depending on the country or region.

Option 2: Individuals convicted for certain crimes or corruption may have restrictions on their voting rights, as determined by the laws of the country or region. In some cases, individuals with felony convictions may temporarily or permanently lose their right to vote.

Option 3: Non-resident citizens typically cannot be registered as voters in the country or region where they are non-resident. Voter registration generally requires residency in order to ensure that individuals have a stake in the local community or governance.

Option 4: Mentally unsound individuals may face restrictions on their right to vote, depending on the laws and regulations of the country or region. These restrictions may vary in terms of severity and the type of mental impairment.

The correct answer is Option 3, as non-resident citizens are generally not eligible for voter registration.