Find the Fourth Derivative Of $y=3 x^{7}+8 x^{6}-9 x^{4}+5 x^{3}-4$
A)

Multiple Choice

Find the fourth derivative of $y=3 x^{7}+8 x^{6}-9 x^{4}+5 x^{3}-4$ .

A) $y^{i v}=7560 x^{2}+7560 x$
B) $y^{i v}=7560 x^{3}+5760 x^{2}-216 x$
C) $y^{i v}=2520 x^{3}+2880 x^{2}-216$
D) $y^{i v}=630 x^{4}+960 x^{3}-216 x+30$