Identify the incorrect statement about OSI layer responsibilities (focus on formatting/translation vs link transfer). Which statement below is wrong?

Introduction / Context: The OSI model separates concerns so that each layer has clear responsibilities. Distinguishing between the Presentation layer (format/translation) and the Transport layer (end-to-end delivery) helps avoid common misconceptions when mapping protocols and services to layers.

Given Data / Assumptions:

• Option (a) assigns translation/formatting to the Transport layer.
• Option (b) assigns translation/formatting to the Presentation layer.
• Option (c) describes the Data Link layer’s role on a single physical link.

Concept / Approach: Presentation (Layer 6) is responsible for data representation: character set translation, encryption/decryption, compression, and syntax marshaling. Transport (Layer 4) provides end-to-end delivery services: segmentation, sequencing, flow and error control, and retransmission. Data Link (Layer 2) manages framing and reliable transfer across a local link between adjacent nodes.

Step-by-Step Solution: Compare option (a) with the OSI definitions: its functions belong to Presentation, not Transport.Confirm option (b) correctly describes the Presentation layer.Confirm option (c) correctly captures the Data Link layer’s responsibility.Therefore, (a) is the incorrect statement.

Verification / Alternative check: Mapping to real protocols: TLS record encoding and content-encoding transformations align with Presentation-layer concepts; TCP’s sequencing and congestion control exemplify Transport-layer duties.

Why Other Options Are Wrong: “All of the above”: Not true because (b) and (c) are correct.

“None of the above”: Not true because (a) is demonstrably incorrect.

Common Pitfalls: Attributing encryption and data format conversion to Transport; while some stacks blur layers, in OSI these are Presentation functions.

Final Answer: The transport layer provides for any format, translation or code conversion necessary to put the data into an intelligible format.