Final answer:
The new input data required by an upgraded system that wasn't needed by the original system most likely pertains to user preferences (A) or data from external sources (C), depending on the new functionalities of the upgrade.
Step-by-step explanation:
Identifying which input data must be obtained by an upgraded system that was not needed by the original system depends on what the new requirements are. Generally, if the new system requires additional functionalities that weren't present in the original, it will need new types of data. For example:
If the upgraded system now has a feature to customize user experiences based on their preferences, it would require A) Data related to user preferences.
Basic functioning of the system (B) Data for basic system functioning) would have been required by both the original and upgraded systems, so it's less likely to be the correct answer.
C) Data from external sources could be needed if the new system integrates with external APIs or services which the original did not.
Last, D) Data for system security might be mandatory if the upgraded system includes new security features or compliance requirements.
Therefore, without additional context on what the upgrade entails, user preferences and external source data are the most likely candidates for additional input data required by the upgraded system.
Therefore, without additional context on what the upgrade entails, user preferences and external source data are the most likely candidates for additional input data required by the upgraded system.