At Which of the Following OSI Model Layers Does the Layer

question 354

Multiple Choice

At which of the following OSI model layers does the Layer 2 Tunneling Protocol operate?

• A) Application
• B) Session
• C) Transport
• D) Data link

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Definitions:

NADH

Nicotinamide adenine dinucleotide (NADH) is a coenzyme found in all living cells, involved in redox reactions and energy production through cellular respiration.

Glycolysis

The metabolic pathway that breaks down glucose into pyruvate, releasing energy and pyruvic acid, occurring in the cytoplasm of cells.

Niacin

Also known as Vitamin B3, it is essential for converting food into energy, maintaining skin health, and supporting the nervous and digestive systems.

Pellagra

A vitamin deficiency disease most commonly caused by a lack of niacin (vitamin B3) in the diet, leading to dermatitis, diarrhea, dementia, and even death if untreated.