question: What is the definition of a file identifier (FID)? option 1: A named and hierarchically-classified data set on the UICC. option 2: The 2-byte name of a file or a directory on the UICC. option 3: The user rate between IWF and the fixed network. option 4: A set of mechanisms used to prevent the network from becoming overloaded by regulating the input rate transmissions. option 5: GERAN feature that allows the channel coding of the layer one to be configured at call setup. 