The correct option is Fixes #210.

Azure Boards recognizes specific closing keywords followed by the numeric work item id with a leading hash. When you include Fixes #210 in the commit message the commit is linked to work item 210 and the bug is transitioned to the Resolved state automatically.

#210 completes is incorrect because "completes" is not a recognized closing keyword for Azure Boards and so it will not trigger the state transition.

Resolves #PROJ-210 is incorrect because Azure Boards expects the plain numeric id prefixed with a hash and does not use a project prefix like PROJ-210. Using Resolves with the correct format such as #210 would be recognized but the PROJ- prefix prevents matching.

Verifies #210 is incorrect because "Verifies" is not one of the recognized keywords that close or resolve work items in Azure Boards.

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