Magento – Create Custom Drop down on registration page

I would like to create custom drop down on all registration pages.
That drop down will have customer from another group.

This is my Pro.php file which is stored in app/code/local/KitchOff/CustomerRegistration/Model/entity and show different dropdown options

<?php 
    class KitchOff_CustomerRegistration_Model_Entity_Pro extends Mage_Eav_Model_Entity_Attribute_Source_Abstract { 
        public function getAllOptions() { 
            if ($this->_options === null) { 
                $this->_options = array(); 
                $this->_options[] = array( 'value' => '', 'label' => 'Choose Option..' ); 
                $this->_options[] = array( 'value' => 1, 'label' => 'Pro1' ); 
                $this->_options[] = array( 'value' => 2, 'label' => 'Pro2' ); 
                $this->_options[] = array( 'value' => 3, 'label' => 'Pro3' ); } 
                return $this->_options; 
            } 
        }
    } 

This is my config.xml which is stored in app/code/local/KitchOff/CustomerRegistration/etc

<?xml version="1.0"?>
<config>
    <modules>
        <KitchOff_CustomerRegistration>
            <version>1.0.0</version>
        </KitchOff_CustomerRegistration>
    </modules>
    <global>
        <helpers>
            <kitchoff_customerregistration>
                <class>KitchOff_CustomerRegistration_Helper</class>
            </kitchoff_customerregistration>
        </helpers>
        <resources>
            <kitchoff_customerregistration_setup>
                <setup>
                    <module>KitchOff_CustomerRegistration</module>
                    <class>Mage_Customer_Model_Resource_Setup</class>
                </setup>
            </kitchoff_customerregistration_setup>
        </resources>
    </global>
</config>

This is my install-1.0.0.php which is stored in app/code/local/CustomerRegistration/sql/kitchoff_customerregistration_setup/
startSetup();

$setup = Mage::getModel('customer/entity_setup', 'core_setup'); 

$setup->addAttribute('customer', 'pro', array( 
    'type' => 'int', 
    'input' => 'select', 
    'label' => 'Select PRO', 
    'global' => 1, 
    'visible' => 1, 
    'required' => 0, 
    'user_defined' => 1, 
    'default' => '0', 
    'visible_on_front' => 1, 
    'source'=> 'customerregistration/entity_pro'
)); 

if (version_compare(Mage::getVersion(), '1.6.0', '<=')) { 
    $customer = Mage::getModel('customer/customer'); 
    $attrSetId = $customer->getResource()->getEntityType()->getDefaultAttributeSetId(); 
    $setup->addAttributeToSet('customer', $attrSetId, 'Customer', 'pro'); 
} 

if (version_compare(Mage::getVersion(), '1.4.2', '>=')) { 
    Mage::getSingleton('eav/config') ->getAttribute('customer', 'pro') ->setData('used_in_forms', array('adminhtml_customer','customer_account_create','customer_account_edit','checkout_register')) ->save(); 
} 

$installer->endSetup(); 

This is my CustomerRegistration.xml which is stored on app/etc/modules

<?xml version="1.0"?>
<config>
    <modules>
        <KitchOff_CustomerRegistration>
            <active>true</active>
            <codePool>local</codePool>
            <depends><Mage_Customer/></depends>
        </KitchOff_CustomerRegistration>
    </modules>
</config>