1. Lose to Shawn Michaels at Wrestlemania 26:
I know that the Wwe wouldn't have Shawn Michaels face the Undertaker at Wrestlemania again if they didn't want HBK to end the Undertaker's streak. I don't think there's anyone else in the business better deserving to end the Undertaker's streak then Shawn Michaels. He's been in the business the same amount of time as the Undertaker has and he's also a legend. I think that at Wrestlemania 26, Shawn Michaels would win and end the Undertaker's streak.
2. Forfeit the streak:
I'm pretty sure that most people don't want to see the Undertaker end his Wrestlemania streak so I think that the Wwe will have declared that the Undertaker's streak ends with him being undefeated but he won't be wrestling at Wrestlemania anymore and will have forfeited the streak. This is one of the choices I don't like but could happen.
3. Lose to one of the up and coming talents:
I think that the Undertaker shouldn't end his prestigious streak to new talent because they haven't been in the business long enough and aren't deserving enough of ending the Undertaker's streak. But on the other side I think that ending the Undertaker's streak could be one of the greatest accomplishments for a young superstar's career and it could be something they could brag about for the rest of their career (if they were a heel).
4. Undertaker get's injured:
This option, just like option 2 ends with Undertaker forfeiting his streak, but this time with a twist. The Undertaker get's injured and can't show up at Wrestlemania. I really hope this option doesn't happen but it still could be one way his streak ends.
5. End the match in controversy:
This is also one of the unlikely choices but I think that they could end the match with controversy. Controversy meaning a DQ or a Countout. If the Wwe does end the match like that then it would end the Undertaker's streak. I think that a arrogant person like Chris Jericho would end the match in controversy and add it to his list of accomplishments such as becoming the first ever undisputed champion and saying that he truly is the best in the world at what he does because he ended the streak