What are the major life moments that define us as human beings?

That question will be asked and possibly answered on Grey's Anatomy Season 10 Episode 20.

Titled "Go It Alone," the installment will reveal whether or not Cristina wins the Harper Avery Award, while Callie and Arizona arrive at a significant decision (via coin clip?) and April has harsh words for Jackson.

Check out the official ABC teaser now:

Look for Derek to also feel overwhelmed by his responsibilities at home and in the hospital during the hour, while Owen accompanies Cristina on her big day.

Will she come out on top?!?

Weigh in now and watch Grey's Anatomy online if you need to catch up prior to next Thursday's episode.

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.