Gap-fill questions

Are fill in the blanks (cloze) questions working for anyone? When I do a question of this type, my quiz won’t load (http://mlsinc.ca/blog/test/).

Has anyone been able to successfully create one of these questions? If you have a moment could you try and create one and see if it works in the preview?

Thanks so much!

https://ww.wp.xz.cn/plugins/wp-pro-quiz/