Find the derivative.

$f(x)=\frac{6}{\sqrt[\phantom{2}]{x}}-\frac{7}{x}\frac{3}{x^5},$ find $f^{\text{'}}(x)$

A$.f^{\text{'}}(x)=-\frac{3}{x^{\frac{3}{2}}}\frac{7}{x^2}-\frac{15}{x^6}$

B$.f^{\text{'}}(x)=-3\sqrt[\phantom{2}]{x}\frac{7}{x^2}-\frac{15}{x^4}$

c$.f^{\text{'}}(x)=\frac{3}{x^{\frac{1}{2}}}-\frac{7}{x^2}-\frac{15}{x^6}$

D$.f^{\text{'}}(x)=-\frac{3}{x^{\frac{3}{2}}}-\frac{7}{x^2}-\frac{15}{x^4}$