The correct answer is D. Functional information subsystems can be classified into input, processing, and output subsystems.
Input subsystems are responsible for collecting data from the environment. Processing subsystems are responsible for transforming the data into information. Output subsystems are responsible for communicating the information to the environment.
Option A is incorrect because it does not include the processing subsystem. Option B is incorrect because it does not include the input subsystem. Option C is incorrect because it does not include the output subsystem. Option E is incorrect because it is not a valid option.