The correct answer is JSON. Vlocity Build Tool, also called the OmniStudio Build Tool in newer documentation, exports and deploys OmniStudio/Vlocity DataPacks in a source-control-friendly structure. A Data Mapper, FlexCard, OmniScript, or Integration Procedure is represented as DataPack metadata, and the component definition is stored in JSON-based files, while job or manifest configuration can use YAML.
DOCX is a document format and has no role in OmniStudio deployment metadata. CSV can hold tabular data, not a full component definition. XML is used in some Salesforce metadata contexts, but DataPacks for OmniStudio deployment are not typically represented as XML component files. Therefore, JSON is the correct deployment metadata format.

The minimum access is the OmniStudio User permission set license plus the OmniStudio User permission set.
This user only executes guided flows; they do not build or modify OmniScripts, FlexCards, Data Mappers, or Integration Procedures. Assigning OmniStudio Admin would over-permission the user because Admin access is intended for users who create and manage OmniStudio components. A developer permission set would also be excessive and is not the minimum runtime configuration. A PSL alone is not enough because it entitles the user to the feature set, while the permission set grants usable permissions. Salesforce permission guidance states that users must have the appropriate OmniStudio permission set assigned, and the OmniStudio User assignment is appropriate for runtime users rather than designers/admins.

The strongest listed choice is a Try-Catch Block, but the real implementation must also use Rollback On Error in the Integration Procedure configuration. Salesforce's OmniStudio training states that Rollback On Error commits database changes only if the entire transaction completes successfully; otherwise, intermediate database changes are rolled back. A Try-Catch Block is used to run steps and catch failures, and with failure handling configured correctly, the failed block can return a controlled error response. A generic Group element only organizes or conditionally runs steps; it does not provide rollback by itself. Chainable processing intentionally splits work into separate transactions, which is the opposite of the requirement. Continue on Error only addresses Data Mapper behavior, not full transaction integrity.

The correct syntax for the Send JSON Path is ActionName: BlockName, where ActionName is the name of the action element and BlockName is the name of the block element that contains the output data. The other options are either missing the colon or using incorrect names.

The Set Values element with a ContextId key/value pair was used for testing purposes and is not needed for production. The developer should delete or deactivate the Set Values element before moving the OmniScript to a production org.