Which one of the following slows down the fast (high-energy) neutrons emitted during fission to energies at which they are more likely to induce fission in a nuclear reaction and thereby helps initiate and sustain a fission chain reaction?

Which one of the following slows down the fast (high-energy) neutrons

1.	Which one of the following slows down the fast (high-energy) neutrons emitted during fission to energies at which they are more likely to induce fission in a nuclear reaction and thereby helps initiate and sustain a fission chain reaction?
A.	Reactor
B.	Moderator
C.	Igniter
D.	Reflector
Answer» C. Igniter