The function of a control panel in a security system is to:

A.
Send alarm signals to a central monitoring center.

B.
Organize the components into a functional system.

C.
Monitoring alarm signals and register reporting on conditions of the alarm system.

D.
Serve as a numeric touch pad allowing the operator to arm and disarm system.

Explanation:
The control panel of a security system is the central unit, touch pads are control devices
where as the panel is the brains where all things come together.