When a coauthored document has a cell with a colored outline around it, what is it suggesting?

Question

(1 point)
Responses

Spellcheck has detected an error.
Spellcheck has detected an error.

The cell is hidden from others’ view.
The cell is hidden from others’ view.

Someone else is working on that cell.
Someone else is working on that cell.

The cell is protected from alterations.
The cell is protected from alterations.

Answer 1

The correct response is:

Someone else is working on that cell.