The best three leading metrics to help NTO measure each reseller's goals through the Partner Community are logins into Partner Community, number of quotes generated, and opportunities generated. These metrics will give NTO early feedback on how the portal is being used by their partners and will provide insight into their success in using the Partner Community. Product types sold and opportunity win rates are lagging metrics and may not provide timely feedback on the success of the Partner Community.
Leading metrics are indicators that show what's happening and can have real-time impact on your bottom line12.
Lagging metrics are indicators that show the outcome of what happened in a previous time period12.
Leading metrics are useful for predicting future performance and making adjustments, while lagging metrics are useful for evaluating past performance and setting goals34.

Option C seems correct because it is important to document all the customizations added to the system, such as code, configuration, integrations, etc., so that they can be easily understood, maintained, and updated by the support team or future developers.
Option D seems correct because it is essential to communicate and train users on new features that are rolled out to support UC's business needs and goals. This can help users adopt the new features faster and more effectively, as well as reduce confusion or frustration.
Option E seems correct because it is advisable to have separate environments for development, training, and production purposes. This can help ensure that new features are developed and tested in a safe and isolated environment before being deployed to the production environment where they can affect real users and data.