@young, Well, if they gave you the wrong fax number or email, your personal info will be floating somewhere out there as well. So I honestly don't understand your point about how fax or email is safer. Any technology is still vulnerable to the user's idiocy.
Regardless of how anyone is planning to submit the documents, its best to do it in a secured manner, such as not using public computers to send private info, or using certified / registered mail with tracking when sending it out via physical mail, etc.
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