A company processes all of its sales orders through a cloud-based system and keeps no manual records. Which control best mitigates the risk that a ransomware attack makes its sales data permanently unavailable?

Correct answer: C) Regular back-ups are held securely, separated from the live network, and restoring data from them is tested periodically

Explanation

Heavy dependence on a single IT system means a cyber attack could destroy or lock the company's records. Secure back-ups kept separately from the live network, with restoration tested, allow the data to be recovered if the live system is compromised. This is a general IT control. Sequential numbering, credit limits and range checks are controls over individual transactions and do nothing to recover lost data.