IPv4 addresses are divided into classes:
Class A: Supports 16,777,214 hosts (large enterprises).
Class B: Supports 65,534 hosts (medium to large networks).
Class C: Supports 254 hosts (small to medium networks).
Class D: Used for multicast, not for assigning IPs to hosts.
Step-by-step Calculation:
The network will have 150 users initially, with a projected growth of 10 users, totaling 160 users.
Each user has two devices, so 160 × 2 = 320 IP addresses needed.
A Class C subnet has 254 usable IPs by default, which is not sufficient.
A Class B subnet can support thousands of hosts, making it the most appropriate option.
Incorrect Options:
A:Class D: Reserved for multicast, not for host assignments.
C:Class A: Overkill for a network of this size.
D:Class C: Cannot support 320 hosts without subnetting, making Class B the best choice.
Reference:
CompTIA Network+ N10-009 Official Study Guide - Chapter on IP Addressing and Subnetting