D Determine Which $x$ -Value Below Is a Solution of the Equation

Multiple Choice

D Determine which $x$ -value below is a solution of the equation $\log _ { 7 } \left( \frac { 5 } { 3 } x \right) = 3$ . $x = \frac { 21 } { 125 } , x = \frac { 1029 } { 5 } , x = \frac { 189 } { 5 } , x = 21 , x = 15$

A) $x = \frac { 21 } { 125 }$
B) $x = \frac { 1029 } { 5 }$
C) $x = \frac { 189 } { 5 }$
D) $x = 21$
E) $x = 15$