Q) Showing your ads on top of the mobile page in search results is beneficial because:

Ans:

Ads above the results get more prominent notice with desktop screens. There are also no ads on the right-hand side of the results on mobile.

Ads below the results get more prominent notice with smaller mobile screens. There are also ads on the right-hand side of  the results on mobile.

Ads above the results get more prominent notice with larger mobile screens. There are also no ads on the right-hand side of the results on mobile.

Ads above the results might get more prominent notice with smaller mobile screens. There are also no ads on the right-hand side of the results on mobile.