Express as the Logarithm of a Single Expression $\log _ { 7 } 6 + \log _ { 7 } 13$

Multiple Choice

Express as the logarithm of a single expression. Assume that variables represent positive numbers.
- $\log _ { 7 } 6 + \log _ { 7 } 13$

A) $\log _ { 14 } 78$
B) $\log _ { 7 } 78$
C) $\log _ { 14 } 19$
D) $\log _ { 7 } 19$