For most large companies using Windows 2000 Active Directory, what is generally the optimum number of Active Directory domains to use in order to simplify network administration while still supporting typical enterprise needs?

Introduction / Context:
This question examines your understanding of Active Directory design principles in Windows 2000 environments. One of the key decisions in designing an Active Directory forest is the number of domains. Microsoft guidance evolved toward fewer domains where possible, because each domain adds complexity in administration, replication, and trust management.

Given Data / Assumptions:

• The company is large but does not have special legal or political constraints that require multiple domains.
• Active Directory is being deployed in a Windows 2000 environment.
• Network administration simplicity is a primary goal.
• Forest and domain concepts are available for hierarchy and delegation.

Concept / Approach:
With Windows 2000 and later, a single domain can support many objects, multiple sites, and flexible organisational units. Organisational units can be used to delegate administration and apply Group Policy in a structured way without creating many separate domains. Additional domains are typically justified only by hard requirements, such as different password policies in older versions, separate schema requirements, or strict security isolation. For most large companies, a single domain design is recommended to minimise complexity and overhead.

Step-by-Step Solution:
Step 1: Consider whether multiple domains are required by technical or legal constraints.Step 2: Recognise that many needs for separation can be achieved with organisational units, Group Policy, and security groups within a single domain.Step 3: Understand that each additional domain adds administrative overhead, trust management, and replication boundaries.Step 4: Choose the option that recommends a single domain as optimal for ease of administration in most large companies.

Verification / Alternative check:
Microsoft best practice documents and exam preparation guides often promote a single domain model with multiple OUs as the default starting point. They advise introducing multiple domains only when there is a clear requirement. Experiences from real enterprises show that excessive domain proliferation leads to complex trust relationships and inconsistent policy application.

Why Other Options Are Wrong:
Option b creates an artificial separation between users and computers that is better handled through OUs. Option c and option d assume that more domains are better for large organisations, which is generally not true in modern Active Directory design. Option e proposes one domain per department, which would be extremely difficult to manage and rarely justified.

Common Pitfalls:
A classic mistake is designing domains based on organisational charts or departments rather than long term technical requirements. Another pitfall is assuming that each geographic site needs its own domain, when sites and OUs can provide location based administration within a single domain. Keeping the domain count low simplifies backups, security, and long term maintenance.

Final Answer:
For most large companies, the optimum number of Active Directory domains is one, because a single domain simplifies administration while still allowing delegation and policy control through organisational units.