We see that in both options the expression we are analyzing is
and we see that the procedure they are trying to apply is to write an equivalent expression that has positive exponents. To do that, we will use the property of exponentiation. Given a non zero number a and any number b, then we have that
So, applying this property to our expression, we have that
Checking our options, we see that the incorrect one is option A. It is wrong because the only expression that should be changed is the one related to the negative exponent