Partial Differentiation Practice

Calculus

If the function $f$ is given by

$f(x,y,z) = xy + \tan\big(x^2 y\big) - z\cos(x) + \log(xz),$

what is the partial derivative $\partial_z f?$

-\cos(x) + \frac{1}{z}

-\cos(x) + \frac{x}{z}

y + 2xy \sec^2(x^2 y) + z\sin (x) + \frac{1}{x}

-z\cos(x) + \log(xz)