Final answer:
The activities of an information system are input, processing, and output.
Step-by-step explanation:
In the context of an information system, the activities can be categorized into three main functions: input, processing, and output.
Input involves the collection or entry of data or information into the system. Processing refers to the manipulation and transformation of the input data to produce meaningful output. Output is the result or response generated by the system based on the processed data.
Therefore, the correct answer is E. input, processing, and output.