Explanation/Reference:
Authentication is based on three factor types: type 1 is something you know, type 2 is something you have and type 3 is something you are. Biometrics are based on the Type 3 authentication mechanism.
Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 2: Access control systems (page 37).

Section: Security Operation Adimnistration
Explanation/Reference:
Actually the term "remanence" comes from electromagnetism, the study of the electromagnetics. Originally referred to (and still does in that field of study) the magnetic flux that remains in a magnetic circuit after an applied magnetomotive force has been removed. Absolutely no way a candidate will see anywhere near that much detail on any similar CISSP question, but having read this, a candidate won't be likely to forget it either.
It is becoming increasingly commonplace for people to buy used computer equipment, such as a hard drive, or router, and find information on the device left there by the previous owner; information they thought had been deleted. This is a classic example of data remanence: the remains of partial or even the entire data set of digital information. Normally, this refers to the data that remain on media after they are written over or degaussed. Data remanence is most common in storage systems but can also occur in memory.
Specialized hardware devices known as degaussers can be used to erase data saved to magnetic media. The measure of the amount of energy needed to reduce the magnetic field on the media to zero is known as coercivity.
It is important to make sure that the coercivity of the degausser is of sufficient strength to meet object reuse requirements when erasing data. If a degausser is used with insufficient coercivity, then a remanence of the data will exist. Remanence is the measure of the existing magnetic field on the media; it is the residue that remains after an object is degaussed or written over.
Data is still recoverable even when the remanence is small. While data remanence exists, there is no assurance of safe object reuse.
Reference(s) used for this question:
Hernandez CISSP, Steven (2012-12-21). Official (ISC)2 Guide to the CISSP CBK, Third Edition ((ISC)2 Press) (Kindle Locations 4207-4210). Auerbach Publications. Kindle Edition.
and
Hernandez CISSP, Steven (2012-12-21). Official (ISC)2 Guide to the CISSP CBK, Third Edition ((ISC)2 Press) (Kindle Locations 19694-19699). Auerbach Publications. Kindle Edition.

The main task here is the authentic distribution of the new root CA certificate as new trust anchor to all the PKI participants (e.g. the users).
In some of the rollover-scenarios there is no automatic way, often explicit assignment of trust from each user is needed, which could be very costly.
Other methods make use of the old root CA certificate for automatic trust establishment (see PKIX-reference), but these solutions works only well for scenarios with currently valid root CA certificates (and not for emergency cases e.g. compromise of the current root CA certificate).
The rollover of the root CA certificate is a specific and delicate problem and therefore are often ignored during PKI deployment.
Reference: Camphausen, I.; Petersen, H.; Stark, C.: Konzepte zum Root CA Zertifikatswechsel, conference Enterprise Security 2002, March 26-27, 2002, Paderborn; RFC 2459 : Internet X.509 Public Key Infrastructure Certificate and CRL Profile.

Section: Network and Telecommunications
Explanation/Reference:
The first types of firewalls were packet filtering firewalls. It is the most basic firewall making access decisions based on ACL's. It will filter traffic based on source IP and port as well as destination IP and port. It does not understand the context of the communication and inspects every single packet one by one without understanding the context of the connection.
"Second generation firewall" is incorrect. The second generation of firewall were Proxy based firewalls. Under proxy based firewall you have Application Level Proxy and also the Circuit-level proxy firewall. The application level proxy is very smart and understand the inner structure of the protocol itself. The Circui-Level Proxy is a generic proxy that allow you to proxy protocols for which you do not have an Application Level Proxy. This is better than allowing a direct connection to the net. Today a great example of this would be the SOCKS protocol.
"Third generation firewall" is incorrect. The third generation firewall is the Stateful Inspection firewall. This type of firewall makes use of a state table to maintain the context of connections being established.
"Fourth generation firewall" is incorrect. The fourth generation firewall is the dynamic packet filtering firewall.
References:
CBK, p. 464
AIO3, pp. 482 - 484
Neither CBK or AIO3 use the generation terminology for firewall types but you will encounter it frequently as a practicing security professional. See http://www.cisco.com/univercd/cc/td/doc/product/iaabu/centri4/user/ scf4ch3.htm for a general discussion of the different generations.

Section: Network and Telecommunications
Explanation/Reference:
High-rate Digital Subscriber Line (HDSL) delivers 1.544 Mbps of bandwidth each way over two copper twisted pairs. SDSL also delivers 1.544 Mbps but over a single copper twisted pair. ADSL and VDSL offer a higher bandwidth downstream than upstream.
Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, John Wiley & Sons, 2001, Chapter 3: Telecommunications and Network Security (page
115).