Which four songs are on the Sonic the Hedgehog Songs Mount Rushmore?

Green Hill Zone
Super Sonic Racing
Live and Learn ...main theme of "SONIC ADVENTURE 2"
HIS WORLD ~THEME OF SONIC THE HEDGEHOG~

I opted for His World because of its overwhelming prominence at the time of the game's release. Other candidates might include:
Chemical Plant Zone
Sonic Boom
Sonic ~ You Can Do Anything
Open Your Heart
Undefeatable