The suggested answer is B, C.
The Environmental Settings within the Workspace Environment Management (WEM) Administration Console are indeed per machine, not per user, meaning that these settings affect all users on the machine uniformly. Additionally, multiple configuration sets are needed when different global settings are required for different agents. This allows for more tailored management of various agent groups within the WEM environment. Therefore, the correct answers are that the Environmental Settings within the WEM Administration Console are per machine, not per user, and multiple configuration sets are needed for different global settings for various agents.