Pick out the correct statement from the following

Options

A. Energy released per unit mass of the reactant is less in case of fusion reaction
B. parcking fraction may be postitive or may be negative
C. `Pu^(239)` is not suitable for a fission reaction
D. for stable nucleus , the specific bonding energy is low

Answer

b

Explanation

Heavy water is uses as moderator in a nuclear reacor. The function of the moderator is to show down the netrons of thermal energies.