Final answer:
To delete a variable record for a single environment, open the Environment record, go to the variables tab, and choose Delete from the dropdown.
Step-by-step explanation:
To delete the variable record for only one environment, the correct steps would be to open the Environment record, navigate to the variables tab, and select Delete from the dropdown. This process ensures that you are managing the configuration settings for the specific environment in question without affecting other environments or the broader system settings.