Select the equivalent expression. \left(\dfrac{3^4}{7^3}\right)^{3}=?( 7 3 3 4 ​ ) 3 =?left parenthesis, start fraction, 3, start superscript, 4, end superscript, divided by, 7, cubed, end fraction, right parenthesis, cubed, equals, question mark Choose 1 answer: Choose 1 answer: (Choice A) A \dfrac37 7 3 ​ start fraction, 3, divided by, 7, end fraction (Choice B) B \dfrac{3^{3}}{7^3} 7 3 3 3 ​ start fraction, 3, cubed, divided by, 7, cubed, end fraction (Choice C) C \dfrac{3^{12}}{7^9} 7 9 3 12 ​ start fraction, 3, start superscript, 12, end superscript, divided by, 7, start superscript, 9, end superscript, end fraction (Choice D) D \dfrac{3^{7}}{7^6} 7 6 3 7 ​ start fraction, 3, start superscript, 7, end superscript, divided by, 7, start superscript, 6, end superscript, end fraction