One of the prohibited act based on the Adsense Terms and Conditions with all the Adsense Publishers is ecouraging someone to generate click on the adsense ads.

Prohibited Uses. You shall not, and shall not authorize or encourage any third party to: (i) directly or indirectly generate queries, Referral Events, or impressions of or clicks on any Ad, Link, Search Result, or Referral Button through any automated, deceptive, fraudulent or other invalid means, including but not limited to through repeated manual clicks, (source)

However, if the ads displayed through Adsense System is the one that said, “CLICK HERE NOW”, then I (as an Adsense Publisher) have no violation on the Adsense Policies if visitors of my site will click on the ad. It’s not me who encourage my visitors to click the ad but the ad itself.
For example, today a banner ad served by the Adsense encouraged my visitors to click into it, as shown on the screenshot below:

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