The correct answers are A, C, and D because the documents prepared before IVS low-level design are the input materials used for design, deployment generation, and parameter definition, while the LLD report is an output of the LLD activity itself. The material emphasizes that network planning must be completed in advance, and the deployment process requires predefined addressing and parameter information. This is consistent with statements such as determining the network segment and IP address range for each network plane before deployment, and with the repeated use of fixed external service and management IP planning in domain and cluster configuration workflows .

From an engineering workflow perspective, the network plan file is required because network segments, IP ranges, and live-network planning must be decided in advance. A project configuration file is also needed because it carries deployment-specific parameters for the project. A JSON file is typically used as a structured import or export artifact generated by design tools and then consumed during planning or deployment preparation. However, the LLD report is not a prerequisite input document; it is the design deliverable produced after engineers complete the LLD work. Therefore, the required pre-LLD preparation documents are A, C, and D .