I open up my updated Minecraft launcher, go to edit profile, change version to 1.7.10, and hit play. I am able to get to the saves menu within Minecraft, but a few seconds after loading up a world, the game crashes.

What I expected to happen was my world to successfully load without a crash report

*What actually happened was any when I tried to load up any world while using an earlier version of Minecraft(below 1.8.0) the game crashed

Steps to Reproduce:
1. Open Minecraft launcher(Everything ok so far)
2. click edit profile, and change version to 1.7.10 (I tried others and the same thing happens with all versions besides 1.8.0+)
3. Press "save Changes" and continue to the PLAY button
4. Enter Minecraft single player saved world menu.
5. Open a saved world, (Loading Chunks)
6. wait for about 3-4 seconds, and then the crash report appears...