OK elders y'all have been around enough you should have good, reasoned opinions about many things. That said; what is your opinion about this:
What are the two most important, fundamental inventions since 1900?
Mind you I said inventions no discoveries. So, discovery of drugs, for example will not qualify. This also would eliminate such thing as "the computer" because computers are not a fundamental since they are merely an adaptation of technology.
Important would be something that literally changed the way we live.