The correct answer is: Controlled processing, inflexibility, rapid response and reliability.
Transaction processing systems must support an organisation's operations (controlled processing) and process every transaction in the same way regardless of user or time (inflexibility).
Fast performance is critical to transaction processing systems. Input must become output in seconds so customers don't wait.
Lastly, transaction processing systems must be reliable as any system failure can potentially stop business. Back-up and recovery procedures must be quick and accurate.
