Quiz archive page shows weird codes

The wp_quiz archive page is showing weird codes:

{“questions”:{“8n1iv”:{“id”:”8n1iv”,”mediaType”:”image”,”answerType”:”text”,”imageCredit”:””,”image”:”https:\/\/factslegend.org\/wp-content\/uploads\/2019\/05\/USA.png”,”imageId”:”17526″,”video”:””,”imagePlaceholder”:””,”imagePlaceholderId”:””,”title”:”English is both the Official and National language of USA.”,”desc”:”English is neither the Official language nor the National language of USA. In fact, the country has no National or Official…

Why is it so?

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