Name three major neutron cross-section categories and what each represents.

• A. Total cross-section is the sum of all scattering cross-sections.
• B. Absorption (Σ_a) – captures; Scattering (Σ_s) – deflects; Fission (Σ_f) – causes fission; Total cross-section Σ_t = Σ_a + Σ_s.
• C. Fission (Σ_f) – suppresses fission processes.
• D. Cross-sections do not depend on energy.

Answer: (B)