What file format is used for theme settings in Shopify?

The correct answer is JSON because Shopify uses JSON (JavaScript Object Notation) as the file format for theme settings. JSON is a lightweight data interchange format that is easy for humans to read and write, and easy for machines to parse and generate. In the context of Shopify themes, settings are defined within a settings_data.json file, allowing theme developers to create customizable options for users in the Shopify admin. This file format facilitates the management and manipulation of structured data for themes in Shopify, ensuring that configuration, preferences, and other customizable aspects are efficiently handled.

Other formats listed, such as XML, HTML, and YAML, are not used for theme settings in Shopify. XML is more verbose and suited for document markup rather than straightforward data interchange, HTML is primarily for structuring web content rather than data management, and YAML, while used in some configurations, is not the standard for Shopify theme settings. Thus, knowing that JSON is specifically utilized for this purpose helps in understanding the overall theme development and customization process in Shopify.