First things first, how did you find your way onto _HP_'s website to ask how to install _Redhat_ RPM's on _AIX_?
I assume you may already know this, but AIX is IBM which falls under the "none of the above" choice (Answer E).
Now to attempt to help you out a little (I am neither an expert on Redhat or AIX) but I assume you are using AIX 5L.
Redhat = Linux
AIX 5L = AIX + Linux
You will want to direct your attention to the Redbooks series located on IBM's website. Below is the link for "Running Linux Applications on AIX"
http://publib-b.boulder.ibm.com/Redbooks.nsf/RedbookAbstracts/sg246033.html?OpenHopefully the message board won't mangle the url too bad. Check out the document, but in my quick "once over" I see that you would use the binary and add the RPM with the rpm command. I don't think that the i386 will be a problem, because I imagine that AIX has mapped the i386 system calls to the corresponding AIX system calls.
HTH
Jeremiah