Estados brasileiros, função em php com estado selecionado

Fala galera,

Fiz essa função básica para gerar estados generica, serve tanto para inserir no banco, como recuperar o estado inserido, segue abaixo o codigo.

Bons codigos.

function estados($id=NULL){
 $html = "<select name='txtEstado' class='form-control' required>"
 . "<option value=''>SELECIONE O ESTADO</option>";
 if($id == "AC") $html.= "<option selected value='AC'>ACRE</option>";
 else $html.="<option value='AC'>ACRE</option>";
 if($id == "AL") $html.= "<option selected value='AL'>ALAGOAS</option>";
 else $html.="<option value='AL'>ALAGOAS</option>";
 if($id == "AM") $html.= "<option selected value='AM'>AMAZONAS</option>";
 else $html.="<option value='AM'>AMAZONAS</option>";
 if($id == "AP") $html.= "<option selected value='AP'>AMAPA</option>";
 else $html.="<option value='AC'>ACRE</option>";
 if($id == "BA") $html.= "<option selected value='BA'>BAHIA</option>";
 else $html.="<option value='BA'>BAHIA</option>";
 if($id == "CE") $html.= "<option selected value='CE'>CEARA</option>";
 else $html.="<option value='CE'>CEARA</option>";
 if($id == "DF") $html.= "<option selected value='DF'>DISTRITO FEDERAL</option>";
 else $html.="<option value='DF'>DISTRITO FEDERAL</option>";
 if($id == "ES") $html.= "<option selected value='ES'>ESPIRITO SANTO</option>";
 else $html.="<option value='ES'>ESPIRITO SANTO</option>";
 if($id == "GO") $html.= "<option selected value='GO'>GOIAS</option>";
 else $html.="<option value='GO'>GOIAS</option>";
 if($id == "MA") $html.= "<option selected value='MA'>MARANHAO</option>";
 else $html.="<option value='MA'>MARANHAO</option>";
 if($id == "MT") $html.= "<option selected value='MT'>MATO GROSSO</option>";
 else $html.="<option value='MT'>MATO GROSSO</option>";
 if($id == "MS") $html.= "<option selected value='MS'>MATO GROSSO DO SUL</option>";
 else $html.="<option value='MS'>MATO GROSSO DO SUL</option>";
 if($id == "MG") $html.= "<option selected value='MG'>MINAS GERAIS</option>";
 else $html.="<option value='MG'>MINAS GERAIS</option>";
 if($id == "PA") $html.= "<option selected value='PA'>PARA</option>";
 else $html.="<option value='PA'>PARA</option>";
 if($id == "PB") $html.= "<option selected value='PB'>PARAIBA</option>";
 else $html.="<option value='PB'>PARAIBA</option>";
 if($id == "PR") $html.= "<option selected value='PR'>PARANA</option>";
 else $html.="<option value='PR'>PARANA</option>";
 if($id == "PE") $html.= "<option selected value='PE'>PERNAMBUCO</option>";
 else $html.="<option value='PE'>PERNAMBUCO</option>";
 if($id == "PI") $html.= "<option selected value='PI'>PIAUI</option>";
 else $html.="<option value='PI'>PIAUI</option>";
 if($id == "RJ") $html.= "<option selected value='RJ'>RIO DE JANEIRO</option>";
 else $html.="<option value='RJ'>RIO DE JANEIRO</option>";
 if($id == "RN") $html.= "<option selected value='RN'>RIO GRANDE DO NORTE</option>";
 else $html.="<option value='RN'>RIO GRANDE DO NORTE</option>";
 if($id == "RO") $html.= "<option selected value='RO'>RONDONIA</option>";
 else $html.="<option value='RO'>RONDONIA</option>";
 if($id == "RS") $html.= "<option selected value='RS'>RIO GRANDE DO SUL</option>";
 else $html.="<option value='RS'>RIO GRANDE DO SUL</option>";
 if($id == "RR") $html.= "<option selected value='RR'>RORAIMA</option>";
 else $html.="<option value='RR'>RORAIMA</option>";
 if($id == "SC") $html.= "<option selected value='SC'>SANTA CATARINA</option>";
 else $html.="<option value='SC'>SANTA CATARINA</option>";
 if($id == "SE") $html.= "<option selected value='SE'>SERGIPE</option>";
 else $html.="<option value='SE'>SERGIPE</option>";
 if($id == "SP") $html.= "<option selected value='SP'>SAO PAULO</option>";
 else $html.="<option value='SP'>SAO PAULO</option>";
 if($id == "TO") $html.= "<option selected value='TO'>TOCANTINS</option>";
 else $html.="<option value='TO'>TOCANTINS</option>";

 $html.="</select>";
 echo $html;
}