The Mayor and each member of the City Council shall have the following qualifications:
(a) be at least twenty-one (21) years of age;
(b) have resided within the city and the territory from which the office is elected for at least twelve (12) months immediately preceding election day;
(c) meet all other eligibility requirements of the Texas Election Code; and
(d) have paid a filing fee of one hundred dollars ($100) or have submitted a petition for candidacy in lieu of a filing fee and said petition must be signed by not less than the greater of (i) twenty-five (25) qualified voters of the territory from which the office is elected or (ii) a number of qualified voters of the territory from which the office is elected equal to one-half of one percent of the total received in said territory by all candidates for Mayor in the most recent Mayoral general election.