please mention that Android and GNU/Linux are entirely different operating systems, except for this one component they share.
if you feel like it, you could start with the question you mentioned, then ask who's using the "linux operating system", then, as people misinformed raise their hands, you tell them not to, because there's no such thing, and then proceed to mention both operating systems that work with it underneath. you might even quote the primary author of Linux:
"Sadly, a kernel by itself gets you nowhere. To get a working system you need a shell, compilers, a library etc. These are separate parts and may be under a stricter (or even looser) copyright. Most of the tools used with linux are GNU software and are under the GNU copyleft."
http://www.kernel.org/pub/linux/kernel/Historic/old-versions/RELNOTES-0.01