Why do we need the protocol and the destination ip info from the 5-tuple to tell the server which application to get the packet?

I learned that in a connection, when the packet arrives at the server, the server will need all the info from the 5-tuple to determine which application will get the package, namely

source ip, source port, destination ip, destination port, protocol(UDP or TCP).

Per my understanding, the source ip, the source port along with the destination port would be enough to determine the "source application"(since there could be only one app that can listen to a particular port at a certain time, if I am right) and the destination port should also tell which service we what from the server. Then I think these three pieces of info would suffice the need of determining which application at the server we should send the package to, then why the protocol and destination ip?

Thanks guys!

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