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.

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