Articles with multiple categories: show the name of 1 category

Hello,
I am managing a site with categories and sub categories. I noticed that on the homepage if each article has multiple categories aesthetically it is not beautiful.

So I would like to show on the home page for each article only the name of 1 category (the primary one or the first of the hierarchy) .. how can I do?

For now I had to hide the names of the categories on the home page by setting display none from css to cat-links

Thanks
Fabrizio

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