(a) A political subdivision must have been in existence for at least 18 months before a local option election to legalize or prohibit the sale of liquor in the political subdivision may be held.
(b) The political subdivision must include substantially all the area encompassed by the political subdivision at the time of its creation and may include any other area subsequently annexed by or added to the political subdivision.
(c) This section does not apply to a municipality incorporated before December 1, 1971.