Because all those energy sources are natural and will always be there, when ever there is a need for extra energy.
The correct option is conscientiousness
<span>Conscientiousness is a big five personality
trait along with extraversion, agreeableness, openness, and neuroticism. Conscientiousness
implies a desire to do a task well and is about how an individual is careful,
thorough or vigilant and direct their impulses.</span>
They are reactants because they are present before the reaction.
