Which of the following is a true statement about the detection of fraud?

Internal controls when properly designed are almost bullet proof in terms of preventing fraud.

Law enforcement plays a significant role in the detection of white collar $($economic$)$ crimes.

For the purposes of understanding how fraud is discovered, whistleblower hotlines are the only method proven to detect fraud.

The combined frequency of tips and accidents in discovering fraud exceeds the combined frequency of internal and external audits.