Which is the most appropriate statement?

Monitoring has been described by COSO as

a. Internal control systems may need to be monitored – a process that assesses the quality of the system’s performance over time. This is accomplished through ongoing monitoring activities, separate evaluations or a combination of the two.

b. Internal control systems need to be monitored – a process that assesses the quality of the system’s performance over time. This is accomplished through ongoing monitoring activities, separate evaluations or a combination of the two.

c. Internal control systems need to be monitored – a process that assesses the quality of the system’s performance over time. This is accomplished through ongoing monitoring activities or separate evaluations.

d. Internal control systems need to be monitored – a compliance process that assesses the quality of the system’s performance over time. This is accomplished through ongoing monitoring activities, separate evaluations or a combination of the two.