It's illegal to send unsolicited credit cards. However, card issuers can -- and do -- contract with credit bureaus to obtain lists of candidates for offers of preapproved credit card accounts. Generally, the bureau uses criteria designed to identify potentially qualified persons, and sells the list to the issuer. The issuer still needs to make the offer and obtain a consumer's agreement.
Consumers can contact the credit bureaus (a single call will cover all three major bureaus) and flag their records as "do not solicit" (don't send my name to an issuer). The FTC site has info on this. Or go to
http://www.experian.com where you'll also find information. Experian is one of the "Big Three."
It's possible that somehow your daughter authorized the issuance. She can still contact the issuer and ask that the account be closed.