<apex:page controller="ColourTableFormat" tabStyle="Account">
<apex:form >
<apex:outputPanel id="out">
<apex:selectCheckboxes value="{!colour}" title ="choose a colour"/>
<apex:pageBlock Title="Colour">
<apex:pageBlockSection title="Colour Summary">
<apex:pageBlockTable value="{!colour}" var="C" columns="3">
<apex:column headerValue="COLOUR"/ >
<apex:selectList value="{!colour}"  Multiselect="false" size="1"/ >
<apex:selectOptions value="{!items}" ></apex:selectOptions>
<apex:actionStatus id="status" startText="testing..."></apex:actionStatus>
</apex:pageBlockTable>
</apex:pageBlockSection>
</apex:pageBlock>
</apex:outputPanel>
</apex:form>
</apex:page>






public class ColourTableFormat
{
   
public boolean checkbox;
public string colour {set;get;}
public integer wavelength {set;get;}
public string description {set;get;}
public list<selectOption> options {get;set;}


public ColourTableFormat()
{
options = new list<selectOption>() ;
checkbox = false;
colour = ' ';
description = ' ';

}
public list<selectOption> getitems()
{
options.add(new selectOption('','----None-----'));
options.add(new selectOption('red','red'));
options.add(new selectOption('green','green'));
options.add(new selectOption('yellow','yellow'));
options.add(new selectOption('','----None-----'));
options.add(new selectOption('15','15'));
options.add(new selectOption('20','20'));
options.add(new selectOption('25','25'));
options.add(new selectOption('','----None-----'));
options.add(new selectOption('Red is the color next to orange at the end of the visible spectrum','Red is the color next to orange at the end of the visible spectrum'));
options.add(new selectOption('Green is the color of nature fertility life','Green is the color of nature fertility life'));
options.add(new selectOption('The color yellow is the color of the mind and the intellect','The color yellow is the color of the mind and the intellect'));

return options;

}
public string getcolour()

{
return colour;
}
public void setcolour()
{
this.colour=colour;
}
}