Question Which is The Best Solid Copper vs Copper Clad Aluminum (CCA)?

CCA is a type of networking cable conductor type
What does the word "network" mean.

Again the standard for ethernet cables that the certification boards define say the wire must be copper.
CCA cable is not allowed to be used for ethernet cables.

A lot of this is very similar to why aluminum cables are not allowed to be used in many electrical wire applications. In that case because it is a safety issue and the rules are set by the government you can get put in jail for selling fake electrical wires.

The standards boards for various computer things are not some large company and do not have massive amounts of money and lawyers to chase all the fake cable.