$\int \tan ^{3} 5 x \sec ^{2} 5 x d x=?$

$\frac{1}{3} s e c^{4} 5 x+C$

$\frac{1}{20} \tan ^{4} 5 x+C$

$\frac{1}{20} \sec ^{4} 5 x+C$

$\frac{1}{12} \sec ^{3} 5 x+C$