You are designing a streaming data solution using Azure Databricks to process sales transaction data from an online store. The solution has the following requirements:

• The output must include the items purchased, quantity, line total sales amount, and line total tax amount.
• The line total sales amount and line total tax amount will be calculated (aggregated) within Databricks.
• Sales transactions are immutable; they are never updated. If an adjustment is needed, a new row is added to the data stream.

You need to recommend a Structured Streaming output mode for the processed dataset. The solution must minimize the presence of duplicate data.

What output mode should you recommend?