Expand into a Sum And/or Difference of Logarithms $\log _ { 7 } x ^ { y }$

Multiple Choice

Expand into a sum and/or difference of logarithms. Assume all variables represent positive real numbers. $\log _ { 7 } x ^ { y }$

A) $\log _ { 7 y } x$
B) $\log _ { 7 } x ^ { \log _ { 7 } y }$
C) $\left( \log _ { 7 } x \right) ^ { y }$
D) $y \log _ { 7 } x$