Solve $\log x + \log ( x - 15 ) = 2$

Multiple Choice

Solve: $\log x + \log ( x - 15 ) = 2$

A) $\left\{ \frac { 500 } { 33 } \right\}$
B) no solution
C) $\{ - 5 \}$
D) $\{ 20 \}$