Which statement defines a fissile material?

Which statement defines a fissile material?

• A. A fissile material is capable of sustaining a nuclear chain reaction by fission upon absorbing a thermal neutron.
• B. A fissile material is any material that can absorb neutrons without fission.
• C. A fissile material is a material that only emits gamma rays.
• D. A fissile material is the material used as a coolant.

Answer: (A)