Choice "C" is correct. A trustee in bankruptcy is treated as a hypothetical lien creditor on all of the debtor's property as of the date the bankruptcy petition is filed. The trustee is subordinate to all prior perfected security interests, including statutory liens that were effective prior to the filing of the bankruptcy petition.
Choice "a" is incorrect. An unperfected security interest would be unprotected against other 3rd parties who had a valid interest in the debtor's property, including the trustee in bankruptcy, because the trustee is treated as a lien creditor as of the date the petition is filed, and a lien creditor prevails against an unperfected security interest.
Choice "d" is incorrect. The trustee in bankruptcy is treated as a lien creditor in the debtor's property as of the date of the filing for bankruptcy. Thus, like any secured creditor, the trustee would have the power to force persons holding the debtor's property to deliver it to the trustee.
Choice "b" is incorrect. Since the trustee becomes a lien creditor in the debtor's property as of the date of the filing, the trustee would have the same rights the debtor would have to obtain the return of the debtor's property.