<?php if( have_rows('prices') ): ?>
<?php while( have_rows('prices') ): the_row(); ?>
<?php
// Get the sub field called "select".
$select = get_sub_field_object('pr_name');
// Get its value.
$value = $select['label'];
// Loop over its choices.
?>
<ul>
<?php foreach( $select['choices'] as $k => $v ): ?>
<li <?php echo ($k === $value) ? 'class="selected"' : ''; ?>>
<?php echo $v; ?>
</li>
<?php endforeach; ?>
</ul>
<?php endwhile; ?>
<?php endif; ?>