निम्नलिखित में से किसे पारंपरिक रूप से 'अंकेक्षण (auditing) की रीढ़' माना जाता है?

Management auditor reports to:

Cost audit is conducted under the direction of:

Under the Companies Act, 2013, internal audit is mandatory for every unlisted public company having a paid-up share capital of at least how much during the preceding financial year?