Insert the missing words:

. . . . . . . . . . . . . . . . . . . . . . . . . . . seeks to establish the degree to which control mechanisms are being applied as prescribed and the results should highlight non-compliance in pursuit of the defined test objective. Often what is meant to happen does not, and procedures that should be in place are ignored.

a. Substantive testing

b. Audit testing

c. Compliance testing

d. Detailed testing