Shopify: Remove sold out options from variant drop down

gistfile1.txt

{% if product.options.size == 1 %} 
  {% for variant in product.variants %}
    {% unless variant.available %}
      jQuery('.single-option-selector option:contains(' + {{ variant.title | json }} +')').remove(); 
    {% endunless %} 
  {% endfor %}
  jQuery('.single-option-selector').trigger('change'); 
{% endif %}