Which of the following transactions is backed by a letter of credit?

Forfaiting is the purchase of a series of credit instruments such as drafts drawn under time, letters of credit, bills of exchange, promissory notes or other freely negotiable instruments on a "non-recourse" basis (non-recourse means that there is no comeback on the exporter if the importer does not pay). The forfaiter deducts interest (in the form of a discount), at an agreed rate for the full credit period covered by the notes.