6. A method as in claim 5 wherein performing the evaluation operations further includes: based on results of the matching operations, providing each variant with a numerical risk score indicating a likelihood that the variant includes sensitive data.
6. A method as in claim 5 wherein performing the evaluation operations further includes: based on results of the matching operations, providing each variant with a numerical risk score indicating a likelihood that the variant includes sensitive data. 8. A method as in claim 6 wherein the content source is a file; and wherein performing the control operation further includes: releasing the file to the destination when all numerical risk scores provided to all of the variants do not exceed the predefined threshold score, and preventing release of the file to the destination when at least one numerical risk score provided to a variant exceeds the predefined threshold score.