Hello, I have a main domain example.com where I have my main content and then I created 3 subdomains one.example.com, two.example.com and three.example.com I think the low ranking of my subdomains is affecting the ranking of my main domain, the one I care the most. So, I decided to get rid of the subdomains. The thing is that only for one.example.com I could transfer the content to my main domain and create 301 redirects. For the other two subdomains I cannot integrate the content in my main domain as it doesn't make sense. Whats the cleanest way to make them dissapear? (just put a redirect to my main domain even if the content is not the same) or just change the robots to "noindex" and put a 404 page in the index of each subdomain. I want to use the way that will harm the least the performance with Google. Regards!