Which of the following are environment conditions in the attribute based access control model, as opposed to subject or object attributes? Choose three.

Answer: A. Where the user is located.
D. The current threat level.
B. The current time of day.

Environment characteristics are independent of subject and object, and SP 800-162 gives current time, day of the week, user location and current threat level. Clearance is a subject attribute.

Source: NIST SP 800-162 (NIST) — SP 800-162 > 2.3 Basic ABAC Concepts