Which of the following is an example of sampling risk?

a) Failing to detect an error on a document that has been inspected by an auditor.
b) Forgetting to apply the finite correction factor in deterring sample size.
c) Concluding that internal controls are not effective when in fact they are effective based on a sample that had multiple cases of control failure.
d) Failing to perform audit procedures that are required by the sampling plan.

Answer: c) Concluding that internal controls are not effective when in fact they are effective based on a sample that had multiple cases of control failure.