An isolated system contains charges $+5\,\text{C}$ and $-5\,\text{C}$. If they are brought together, which statement is correct?

Principle: total electric charge in an isolated system remains conserved. Here the initial total charge is $+5 + (-5) = 0\,\text{C}$. Bringing the charges together may allow neutralization in effect, but it does not mean charge is destroyed; the algebraic total remains zero throughout. Option A is tempting because students often say charges 'cancel out' by vanishing, but conservation means they do not disappear. Options C and D incorrectly add charges without regard to sign.