To delete the variable record for only one environment, which record needs to be opened?

To delete the variable record for only one environment, the Environment record needs to be opened. This is because the Environment record is specifically designed to contain settings, configurations, and variables that are unique to that particular environment. By accessing the Environment record, you can directly manage and modify the variables associated with it, including deleting any unwanted variable records.

The other options do not offer the granularity required to manage environment-specific variables. Environment Variables is a broader category that typically encompasses all environments and their variables without focusing on a single environment. The Pipeline represents the workflow for your deployments and is not directly related to individual environment configurations. Metadata Files pertain to the structures and data definitions but do not specifically handle the variable records tied to an environment. Therefore, the Environment record is necessary for precise control over environment-specific variables.