Answer
$ \displaystyle \log\frac{a}{b^{2}c}$
Work Step by Step
... Group the negative terms (factor out -1)
$...=\log a-(2\log b+\log c)\quad$... Apply the property $\log_{a}M^{p}=p\cdot\log_{a}M$
$=\log a-(\log b^{2}+\log c)\quad$... Apply the property $\log_{a}(MN)=\log_{a}M+\log_{a}N$
$=\log a-\log(b^{2}c)\quad$... Apply the property $\displaystyle \log_{a}\frac{M}{N}=\log_{a}M-\log_{a}N$
$=\displaystyle \log\frac{a}{b^{2}c}$