In Snowflake notebooks, the user interface provides visual cues for the execution status of each cell. A red checkmark specifically indicates that the cell's execution resulted in an error. This allows users to quickly identify and troubleshoot problematic code blocks within their notebook. In contrast, a green checkmark signifies successful completion, and a spinning icon indicates the cell is currently running.

B. A running cell is indicated by a spinning progress icon, not a red checkmark, which signifies a completed (but failed) state.

C. Successful completion is indicated by a green checkmark, which is visually distinct from the red checkmark for errors.

D. A paused state is not a standard cell status in Snowflake notebooks; the red checkmark indicates a terminal failure state.

- Snowflake Documentation. (n.d.). Develop apps with Snowflake Notebooks. In Developer Guide. Retrieved from https://docs.snowflake.com/en/developer-guide/notebooks/notebook-develop. Under the section "Run cells in a notebook," the documentation states: "When the cell finishes running, an icon appears to the left of the cell. A green checkmark indicates that the cell ran successfully. A red checkmark indicates that the cell ran with an error."