How do coinmarketcap.com google ads only shows ads related to ICO coin?

[puremage111]

Hello, for those who have used https://coinmarketcap.com to check the price of a coin, trading volume of coin.

Whoever have use google adsense before can answer me, how they did that?

I mean even on other sites, my google ads will shows about Forex, Shopping sites which relates to me.

But coinmarketcap shows all the ICO coins, alt coin and so, is there idea for it?