Class addresses D and E are not allotted to hosts. Class D addresses are reserved for multicasting, and their address range can extend from 224 to 239. Class E addresses are reserved for experimental purposes. Their addresses range from 240 to 254. Answer option C is incorrect. Class A addresses are specified for large networks. It consists of up to 16,777,214 client devices (hosts), and their address range can extend from 1 to 126. Answer option D is incorrect. Class B addresses are specified for medium size networks. It consists of up to 65,534 client devices, and their address range can extend from 128 to 191. Answer option A is incorrect. Class C addresses are specified for small local area networks (LANs). It consists of up to 245 client devices, and their address range can extend from 192 to
223.

SMTP relay feature of e-mail servers allows them to forward e-mail to other e-mail servers. Unfortunately, this
feature is exploited by spammers and worms to generate spam on the Internet.

Contingency plan is prepared and documented for emergency response, backup operations, and recovery
maintained by an activity as the element of its security program that will ensure the availability of critical
resources and facilitates the continuity of operations in an emergency situation.
A contingency plan is a plan devised for a specific situation when things could go wrong. Contingency plans are
often devised by governments or businesses who want to be prepared for anything that could happen.
Contingency plans include specific strategies and actions to deal with
specific variances to assumptions resulting in a particular problem, emergency, or state of affairs. They also
include a monitoring process and "triggers" for initiating planned actions. They are required to help
governments, businesses, or individuals to recover from serious incidents in
the minimum time with minimum cost and disruption.
Answer option B is incorrect. A disaster recovery plan should contain data, hardware, and software that can be
critical for a business. It should also include the plan for sudden loss such as hard disc crash. The business
should use backup and data recovery utilities to limit the loss of data.
Answer option D is incorrect. The Continuity Of Operation Plan (COOP) refers to the preparations and
institutions maintained by the United States government, providing survival of federal government operations in
the case of catastrophic events. It provides procedures and capabilities to sustain an organization's essential.
COOP is the procedure documented to ensure persistent critical operations throughout any period where
normal operations are unattainable.
Answer option C is incorrect. Business Continuity Planning (BCP) is the creation and validation of a practiced
logistical plan for how an organization will recover and restore partially or completely interrupted critical (urgent)
functions within a predetermined time after a disaster or extended disruption. The logistical plan is called a
business continuity plan.