Depends on what you want to do with the other 3 ISP connections. The problem arises that the ASA is only able to have 1 active default route. So you could have 3 ISP connections setup but internet traffic would only be able to be used on one of those links. You could set up 2 more default routes for those connection so when the first ISP fails the second default route will take over and so on.
You can however, use one link for internet with the default route and if you want the other ISP links to only access certain IP ranges you can add static routes pointing out those interfaces to reach those networks.
But in short, you can only use one of those ISP links for internet traffic.
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