AdSense is a pay-per-click advertising program, therefore the best topic for an AdSense-ready blog would be one with high traffic and a targeted audience interested in the products or services being advertised. Some of the most profitable niches for AdSense include:
1) Finance
2) Health & Wellness
3) Technology & Gadgets
4) Food & Recipes
5) Personal Development & Self-Improvement
6) Travel & Tourism
7) Home & Garden
8) Fashion & Beauty
9) Parenting & Family
10) Sports & Fitness
It's important to note that while these niches have proven to be profitable, there is no guarantee of success, and it's important to choose a topic that you're passionate about and can create high-quality content for.