Answer: At least one notebook library to be executed

When creating a new Delta Live Tables pipeline, the only mandatory requirement is to specify at least one notebook library to be executed. This notebook contains the pipeline logic and transformations. The other options are either optional or not required: - **A. A key-value pair configuration**: Optional - configurations can be set but are not mandatory - **B. The preferred DBU/hour cost**: Not required - cost management is handled differently - **C. A path to cloud storage location for the written data**: Optional - storage locations can be configured but have defaults - **D. A location of a target database for the written data**: Optional - database locations can be configured but have defaults According to Databricks documentation, the minimum requirement is to specify at least one notebook library that contains the pipeline code to be executed.

Author: Keng Suppaseth