Insert the missing phrase (this phrase applies to both gaps):

Recommendations must be based on . . . . . . . . . . . . . . . . . . . . . . . . . and the extent of this supporting material depends on the importance of establishing the effects of control weaknesses. Where internal auditors are required to attend management working parties which publish reports and make recommendations without comprehensive research then their views should be qualified as not being derived from the normal audit process. The formal audit reports in contrast must be based on . . . . . . . . . . . . . . . . . . . . . . . . . that has been derived from the audit process.

a. sound evidence

b. intuition

c. the auditor’s knowledge

d. agreed ways forward