Which statement is most appropriate?

Our definition of the audit manual is:

a. A report that involves the accumulation and dissemination of all those documents, guidance, direction and instructions issued by audit management that affect the way the audit service is delivered.

b. A document that involves the accumulation and dissemination of all those documents, guidance, direction and instructions issued by audit management that affect the way the audit service is delivered.

c. A device that involves the accumulation and dissemination of all those documents, guidance, direction and instructions issued by audit management that affect the way the audit service is managed.

d. A device that involves the accumulation and dissemination of all those documents, guidance, direction and instructions issued by audit management that affect the way the auditor behaves.