Explanation

Configuration management isn't about preventing change but ensuring the integrity of IT resources by preventing unauthorised or improper changes.
According to the Official ISC2 guide to the CISSP exam, a good CM process is one that can:
(1)
accommodate change;
(2)
accommodate the reuse of proven standards and best practices;
(3)
ensure that all requirements remain clear, concise, and valid;
(4)
ensure changes, standards, and requirements are communicated promptly and precisely; and
(5)
ensure that the results conform to each instance of the product.
Configuration management Configuration management (CM) is the detailed recording and updating of information that describes an enterprise's computer systems and networks, including all hardware and software components. Such information typically includes the versions and updates that have been applied to installed software packages and the locations and network addresses of hardware devices. Special configuration management software is available. When a system needs a hardware or software upgrade, a computer technician can accesses the configuration management program and database to see what is currently installed. The technician can then make a more informed decision about the upgrade needed. An advantage of a configuration management application is that the entire collection of systems can be reviewed to make sure any changes made to one system do not adversely affect any of the other systems
Configuration management is also used in software development, where it is called Unified Configuration Management (UCM). Using UCM, developers can keep track of the source code, documentation, problems, changes requested, and changes made. Change management In a computer system environment, change management refers to a systematic approach to keeping track of the details of the system (for example, what operating system release is running on each computer and which fixes have been applied).

Explanation/Reference:
Explanation:
On-line network-based IDS monitors network traffic in real time and it analyses the Ethernet packet and applies it on the same rules to decide if it is an attack or not.
Incorrect Answers:
B: A host-based intrusion detection system (HIDS) monitors and analyzes the internals of a computing system, as well as the network packets on its network interfaces in certain instances.
C: An application-based IDS is designed to monitor a specific application.
D: Firewalls are different to IDS because it looks outwardly for intrusions in order to stop them from happening.
References:
https://en.wikipedia.org/wiki/Intrusion_detection_system
https://en.wikipedia.org/wiki/Host-based_intrusion_detection_system

"The main difference between memory cards and smart cards is the processing power. A memory card holds information, but does not process information. A smart card has the necessary hardware and logic to actually process information." Pg 121 Shon Harris CISSP All-In-One Exam Guide