Answer:
Choice B is correct
Explanation:
Using the properties of exponents the expression can be simplified so as to eliminate the negative powers;
![a^(-2)=(1)/(a^(2) )](https://img.qammunity.org/2020/formulas/mathematics/high-school/ovi609a4l8j6g8im9uw1khxetbx35l88e9.png)
This component thus shifts to the denominator
![a^(-7)=(1)/(a^(7) )](https://img.qammunity.org/2020/formulas/mathematics/high-school/10ictzt8qmlsqwwoey8a28hibo19ttsfta.png)
This component thus shifts to the numerator
![b^(-1)=(1)/(b)](https://img.qammunity.org/2020/formulas/mathematics/high-school/6myum7cw0eyuuml92o4tlkvqjtba3f00u4.png)
This component thus shifts to the numerator
The final simplified expression is thus B