Use Properties of Logarithms to Condense the Logarithmic Expression $3 \log 54 + \frac { 1 } { 6 } \log 5 ( r - 7 ) - \frac { 1 } { 2 } \log 5 r$

Multiple Choice

Use properties of logarithms to condense the logarithmic expression. Write the expression as a single logarithm
whose coefficient is 1. Where possible, evaluate logarithmic expressions.
- $3 \log 54 + \frac { 1 } { 6 } \log 5 ( r - 7 ) - \frac { 1 } { 2 } \log 5 r$

A) $\log _ { 5 } \frac { 64 \sqrt [ 6 ] { r - 7 } } { \sqrt { r } }$
B) $\log 5 \frac { 64 r - 7 } { 12 r }$
C) $\log _ { 5 } \sqrt { \frac { 3 \mathrm { r } - 21 } { 12 \mathrm { r } } }$
D) $\log _ { 5 } \left( \frac { 1 } { 4 } \sqrt { \frac { \mathrm { r } - 7 } { \mathrm { r } } } \right)$