Which of the following best describes the function of a red clause letter of credit?

	a.	To indicate to the exporter that a problem has occurred with the importer's finance instruments, and signal the need to renegotiate.
	b.	To highlight specific terms struck between the importer and the exporter that are outside of the standard negotiations used with letters of credit.
	c.	To authorize the advising bank to make advances to the exporter against the guarantee of the importer's bank.
	d.	To indicate the exact number of times a revolving documentary letter of credit may be renewed.