Once you enable the one word answers module, quality check will be done against the responses which have multiple row text questions or comment questions. If the respondent has provided one word answer which is less than or equal to 3 charcters (e.g. yes, no, ok) that response will be flagged.
Go to: Login » Surveys (Select Survey) » Analytics » Manage Data
Under Manage Data, select Data Quality option.
Enable Data Quality and enable one word answers module.
Go to: Login » Surveys (Select Survey) » Analytics » Responses
Under Responses, click on Response ID with flag Icon
If you think the response should not have been flagged, you can unflag the response. To unflag a response click on the Response ID. Navigate to data quality tab. This view will provide question, answer and the reason for flagging a response. Click on the Unflag Response button. Once a response is unflagged, flag icon will disappear in the response viewer.
To flag the response, click on Response ID. This will take you to data quality tab where you can click on Flag Response button. Once the response is flagged, it will appear under Flagged Responses tab in audience view and in surveys, flag icon will appear with Response ID which has been flagged.