Both $\ln$ and $e^x$ are monotonically (continuously) increasing functions. So, (i) and (ii) are TRUE.
If we take $x = 3, y = 2;y^x = 8, x^y = 9.$ So, (iii) is false
$\cos x$ is not a monotonically increasing function. So, (iv) is false.
Correct Option: A