Which three elements help network designers to construct secure systems that protect information and resources...

A (Confidentiality): Protects information from unauthorized access.

D (Availability): Ensures resources are accessible when needed.

E (Integrity): Ensures data is not tampered with or altered improperly.

These three form the core of information security design principles known as the CIA triad (Confidentiality, Integrity, Availability), directly referenced in CCDE v3.1 security design sections.

Why other options are incorrect:

B, C, F: While important for network design, they are not part of the core security protection objectives.

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