After clicking on one of those buttons you can determine where the copy should be inserted.
The copy can be pasted within the same survey. You can choose the exact place where it should be inserted (yellow circles). It is also possible to transfer a copy to another, editable survey (red circle). Therefore you need at least one other survey in your account, which is not active and has not expired.
You are also able to duplicate an entire survey:
The status (active, interrupt, closed) of the questionnaire that needs to be copied is irrelevant. Even an expired survey can be copied, edited and relaunched. But the results of the original survey will not be adopted.