Which of these is NOT an OSI network layer?

Which of these is NOT an OSI network layer?

• The Security Layer
• The Transport Layer
• The Application Layer
• The Physical Layer 

EXPLANATION

The Open System Interconnection (OSI) model defines a networking framework to implement protocols in seven layers.
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The 7 Layers of the OSI

1. Layer 1 - Physical.
2. Layer 2 - Data Link.
3. Layer 3 - Network.
4. Layer 4 - Transport.
5. Layer 5 - Session.
6. Layer 6 - Presentation.
7. Layer 7 - Application.