metabox values form grouped checkboxes

this is my meta box grouped checkboxes
array (
‘label’ => ‘Checkbox Group’,
‘desc’ => ‘A description for the field.’,
‘id’ => $prefix.’checkbox_group’,
‘type’ => ‘checkbox_group’,
‘options’ => array (
‘one’ => array (
‘label’ => ‘Option One’,
‘value’ => ‘one’
),
‘two’ => array (
‘label’ => ‘Option Two’,
‘value’ => ‘two’
),
‘three’ => array (
‘label’ => ‘Option Three’,
‘value’ => ‘three’
)
)
),

how to return values form this gruoped checkboxes, values from: option one, option two, and option three