Explanation/Reference:
Explanation:
Packet filtering is a firewall technology that makes access decisions based upon network-level protocol header values. The filters can make access decisions based upon the following basic criteria:
Source and destination port numbers (such as an application port or a service number)

Protocol types

Source and destination IP addresses

Inbound and outbound traffic direction

Incorrect Answers:
B: A packet filtering firewall can grant access to desired services, not dedicated services, through source and destination numbers.
C: A packet filtering firewall can grant access to desired services, not delayed services, through source and destination numbers.
D: A packet filtering firewall can grant access to desired services, not distributed services, through source and destination numbers.
References:
Harris, Shon, All In One CISSP Exam Guide, 6th Edition, McGraw-Hill, New York, 2013, p. 630