Try:
perl -ne"chomp; print $_,',',(split ',',<STDIN>)[-1]" in1.csv < in2.cs
+v >out.csv
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.