In nuclear fission and fusion the mass defect is
A) the mass of the reactants that break apart.
Eliminate
B) the mass that canot be found inside the nucleus.
C) the mass lost during the reaction that is converted into energy.
D) the mass that is needed to start the fission or fusion reaction.

Option C

In nuclear fission and fusion the mass defect is the mass lost during the reaction that is converted into energy

Explanation:

Mass defect is the contrast within the estimated mass of the released system and the empirically estimated mass of the nucleus. The nuclear binding energy is acknowledged as mass, and that mass enhances "missing".

This missing mass is described as a mass defect, which is nuclear energy, also acknowledged as the mass discharged from the reaction as any trajectories. The mass defect of a nucleus depicts the mass of the energy adhesive of the nucleus and is the variation amidst the mass of a nucleus and the entirety of the masses of the nucleons of which it is comprised.

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