Border Patrol Agents may seize and retain an encountered electronic device or copies of information from the device when, based on a review of the device, they determine that there is probable cause to believe that the device contains evidence of a violation of a law that CBP is authorized to enforce.

From the information given above, it can be validy conduded that

A$)$ if an Agent may not seize and retain an encountered electronic device, then the Agent has determined that the device does not contain evidence of a violation of a law that $CBP$ is authorized to enforce

B$)$ there are cases in which an Agent who has determined that an encountered electronic device may contain evidence of a violation of a law enforced by CBP may not seize and retain the device

C$)$ it may well be the case that an Agent will seize and retain a device that the Agent initially determined may not contain any evidence of a legal violation

D$)$ if an Agent may seize and retain an encountered electronic device, then the Agent has not necessarily determined that the device contains evidence of a legal violation

E$)$ there are at least some cases in which an Agent who determines that an encountered device may not contain evidence of a violation of law may seize and retain the device