//Change Choose an option

function my_dropdown_variation_attribute_options_html($html, $args){
$html = str_replace(‘Choose an option’, ‘Options’, $html);
return $html;
}
add_filter(‘woocommerce_dropdown_variation_attribute_options_html’, ‘my_dropdown_variation_attribute_options_html’, 10, 2);

 

Add it to functions.php