Many websites place a large rectangle Adsense ad unit just below the post title because it is the best performing ad.

However, in Adsense Guidelines (Not in their ToS or in the Hit Map), it is written very clearly that it is not acceptable - Blending an ad is not allowed as it misleads the reader:

1. Ads shouldn’t be placed under a title or section heading in a way that implies that the ads are not ads.
2. Ads should be easily distinguishable from surrounding content.
[adsense.blogspot.com ]

Since many accounts are disabled lately because of invalid clicks or encouraging click activity, this ad unit could become a make or break for publishers.

How do you distinguish this ad unit from the rest of the site?
Some ideas would be:

Locating the ad under the post title, 3 options:
A. Wrap this ad around body content to left or right.
B. Place it at the center leaving white spaces at right and left.
C. Align it to the left leaving white space at the right?

Make it distinguished:
A. Use different background and different link/text colors to this ad unit?
B. Create a border around the ad? Meaning, using the same color scheme for the ad colors, but making the ad separate by means of a clear border so its obvious it is not part of the content.
C. Labeling the ad unit - Advertisements, Sponsored ads or Ads by Google

What could be considered acceptable?
I'd appreciate if anyone from Google Quality Department contribute their suggestion here.
Thanks