Which statement best describes the meaning of supercritical, critical, and subcritical states in terms of neutron population?

• A. Neutron population remains constant over time.
• B. Supercritical → neutron population grows; Critical → stable; Subcritical → decays toward zero.
• C. Neutron population decays to zero regardless of reactivity.
• D. All three states refer to reactor temperature rather than neutron population.

Answer: (B)