Section: Network and Telecommunications
Explanation/Reference:
PPTP is an encapsulation protocol based on PPP that works at OSI layer 2 (Data Link) and that enables a single point-to-point connection, usually between a client and a server.
While PPTP depends on IP to establish its connection.
As currently implemented, PPTP encapsulates PPP packets using a modified version of the generic routing encapsulation (GRE) protocol, which gives PPTP to the flexibility of handling protocols other than IP, such as IPX and NETBEUI over IP networks.
PPTP does have some limitations:
It does not provide strong encryption for protecting data, nor does it support any token-based methods for authenticating users.
L2TP is derived from L2F and PPTP, not the opposite.

Explanation/Reference:
SMTP (Simple Mail Transfer Protocol) works as a message transfer agent.
Source: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2001, Page
821.

Section: Risk, Response and Recovery
Explanation/Reference:
A Full Backup must be made regardless of whether Differential or Incremental methods are used.
Source: KRUTZ, Ronald L. & VINES, Russel D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 69.
And: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2002, chapter 9:
Disaster Recovery and Business continuity (pages 617-619).

Transmission on fiber optic wire requires repeating at distance intervals. The glass fiber requires more protection within an outer cable than copper. For these reasons and because the installation of any new wiring is labor-intensive, few communities yet have fiber optic wires or cables from the phone company's branch office to local customers (local loop).
In telephony, a local loop is the wired connection from a telephone company's central office in a locality to its customers' telephones at homes and businesses. This connection is usually on a pair of copper wires called twisted pair. The system was originally designed for voice transmission only using analog transmission technology on a single voice channel. Today, your computer's modem makes the conversion between analog signals and digital signals. With Integrated Services Digital Network (ISDN) or Digital Subscriber Line (DSL), the local loop can carry digital signals directly and at a much higher bandwidth than they do for voice only.
Local Loop diagram

Image from: http://www.thenetworkencyclopedia.com/entry/local-loop/
The following are incorrect answers:
New loop This is only a detractor and does not exist
Loopback In telephone systems, a loopback is a test signal sent to a network destination
that is returned as received to the originator. The returned signal may help diagnose a problem. Ingenious loop This is only a detractor and does not exist
Reference(s) used for this question:
http://searchnetworking.techtarget.com/definition/local-loop and STEINER, Kurt, Telecommunications and Network Security, Version 1, May 2002, CISSP Open Study Group (Domain Leader: skottikus), Page 14.

Explanation/Reference:
Although a loss of skilled workers knowledge would cause the company a great loss, it is not identified as a specific loss criteria. It would fall under one of the three other criteria listed as distracters.
Source: HARRIS, Shon, All-In-One CISSP Certification Exam Guide, McGraw-Hill/Osborne, 2002, chapter
9: Disaster Recovery and Business continuity (page 598).