int applicantAge = -5;
try
{
    VerifyVoterEligibility(applicantAge);
}
catch (ArgumentException ex)
{
    Console.WriteLine(ex.Message);
}
finally
{
    Console.WriteLine("Verification process finished.");
}
// --- Helper Method ---
void VerifyVoterEligibility(int age)
{
    if (age < 0)
    {
        throw new ArgumentException("Age cannot be negative.");
    }
    
    if (age >= 18)
    {
        Console.WriteLine("Eligible to vote.");
    }
    else
    {
        Console.WriteLine("Not eligible to vote.");
    }
}