Watir: Select an item in checkbox - ruby

Question

I am using watir-webdriver, I am trying to select one box from the HTML code below, for example "LC" for the input but I am having some troble to get it work. Anyone have any idea please. thanks
browser.checkbox(:value => 'LC').set
error message
C:/Ruby193/lib/ruby/gems/1.9.1/gems/watir-2.0.4/lib/watir/element.rb:78:in `asse
rt_exists': Unable to locate element, using {:value=>"LC"} (Watir::Exception::Un
knownObjectException)
code
<TD align="right">Reason: </TD>
<TD><style type="text/css">
select, ul { height: 40px; overflow: auto; width: 205px; border: 1px solid #000; }
ul { list-style: none; margin: 0; padding: 0; overflow-x: hidden;}
li { margin: 0; padding: 0; }
ul li {
position: relative;
}
li ul {
position: absolute;
left: 149px;
top: 0;
display: none;
}
label { display: block; color: WindowText; background-color: Window; margin:0;
padding:0; width: 100%; }
label:hover { background-color: Highlight; color: HighlightText; display: block; }
</style>
<script type="text/javascript">
function appendValue(checkedValue) {
findFormElement("reason").value = ""
if(document.getElementById("CS").checked){
findFormElement("reason").value= findFormElemen"reason").value+document.getElementById ("CS").id;
}
if(document.getElementById("LC").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("LC").id;
}
if(document.getElementById("ND").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("ND").id;
}
if(document.getElementById("NG").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("NG").id;
}
if(document.getElementById("NC").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("NC").id;
}
if(document.getElementById("WD").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("WD").id;
}
};
</script>
<input name="reason" type="hidden" value></select><ul id="multisel">
<li><label for="CS"><input type="checkbox" name="CS" id="CS" onClick="appendValue ("CS")"/>Cannot Supply Within 2 Hours</label></li>
<li><label for="LC"><input type="checkbox" name="LC" id="LC" onClick="appendValue("LC")"/>Location Closed</label></li>
<li><label for="ND"><input type="checkbox" name="ND" id="ND" onClick="appendValue("ND")"/>No Drivers Available</label></li>
<li><label for="NG"><input type="checkbox" name="NG" id="NG" onClick="appendValue("NG")"/>No Vehicle Group Available</label></li>
<li><label for="NC"><input type="checkbox" name="NC" id="NC" onClick="appendValue("NC")"/>No Vehicles Available</label></li>
<li><label for="WD"><input type="checkbox" name="WD" id="WD" onClick="appendValue("WD")"/>Weekend Delivery</label></li>
</ul></TD>
select, ul { height: 40px; overflow: auto; width: 205px; border: 1px solid #000; }
ul { list-style: none; margin: 0; padding: 0; overflow-x: hidden;}
li { margin: 0; padding: 0; }
ul li {
position: relative;
}
li ul {
position: absolute;
left: 149px;
top: 0;
display: none;
}
label { display: block; color: WindowText; background-color: Window; margin: 0; padding: 0; width: 100%; }
label:hover { background-color: Highlight; color: HighlightText; display: block; }
</style>
<script type="text/javascript">
function appendValue(checkedValue) {
findFormElement("reason").value = ""
if(document.getElementById("CS").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("CS").id;
}
if(document.getElementById("LC").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("LC").id;
}
if(document.getElementById("ND").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("ND").id;
}
if(document.getElementById("NG").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("NG").id;
}
if(document.getElementById("NC").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("NC").id;
}
if(document.getElementById("WD").checked){
findFormElement("reason").value = findFormElement("reason").value + document.getElementById("WD").id;
}
};
</script>
<input name="reason" type="hidden" value></select><ul id="multisel">
<li><label for="CS"><input type="checkbox" name="CS" id="CS" onClick="appendValue ("CS")"/>Cannot Supply Within 2 Hours</label></li>
<li><label for="LC"><input type="checkbox" name="LC" id="LC" onClick="appendValue("LC")"/>Location Closed</label></li>
<li><label for="ND"><input type="checkbox" name="ND" id="ND" onClick="appendValue("ND")"/>No Drivers Available</label></li>
<li><label for="NG"><input type="checkbox" name="NG" id="NG" onClick="appendValue("NG")"/>No Vehicle Group Available</label></li>
<li><label for="NC"><input type="checkbox" name="NC" id="NC" onClick="appendValue("NC")"/>No Vehicles Available</label></li>
<li><label for="WD"><input type="checkbox" name="WD" id="WD" onClick="appendValue("WD")"/>Weekend Delivery</label></li>
</ul></TD>

Answer 1

The checkboxes don't have a value; however they each have an id. Try
browser.checkbox(:id => 'LC').set

Answer 2

In case you ended up here wanting to unselect the checbox, the method is clear