Answer: Layer 6 (Presentation layer)
Explanation: OSI(Open Systems Interconnection ) architecture is the model that contains 7 layers , in which the layer 6 (Presentation layer) is the layer that can work with the ASCII codes .Presentation layer is responsible for the translation of the data in the system network.
This layer standardizes and formats the data so that it can be presented and forwarded on the Application layer.It can function for the compressing of data, encrypting ,decryption and other formatting functions.