Thank you for your answer!
It solves the Conditional statement.
But how to display selected values labels?
I tried echo $value; but it displays only “Array”.
I checked the doc: http://www.advancedcustomfields.com/resources/checkbox and find this:
/*
* Displaying a single value's Label
*/
$field = get_field_object('field_name');
$value = get_field('field_name');
$label = $field['choices'][ $value ];
But I don’t understand how the $label works? Where [‘choices’] comes from?