Minecraft Beta 1.7.3 Crash Error : java.lang.ArrayIndexOutOfBoundsException: 6

Minecraft has crashed!
----------------------

Minecraft has stopped running because it encountered a problem.

If you wish to report this, please copy this entire text and email it to support@mojang.com.
Please include a description of what you did when the error occured.



--- BEGIN ERROR REPORT a1dce528 --------
Generated 11.01.20 18:06

Minecraft: Minecraft Beta 1.7.3
OS: Windows 10 (amd64) version 10.0
Java: 1.8.0_51, Oracle Corporation
VM: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
LWJGL: 2.9.0
OpenGL: Intel(R) UHD Graphics 620 version 4.5.0 - Build 24.20.100.6293, Intel

java.lang.ArrayIndexOutOfBoundsException: 6
at kv.c(SourceFile:253)
at nj.b(SourceFile:30)
at da.a(SourceFile:95)
at net.minecraft.client.Minecraft.a(SourceFile:540)
at co.a(SourceFile:51)
at da.a(SourceFile:72)
at da.f(SourceFile:120)
at da.e(SourceFile:108)
at net.minecraft.client.Minecraft.k(SourceFile:1299)
at net.minecraft.client.Minecraft.run(SourceFile:754)
at java.lang.Thread.run(Thread.java:745)
--- END ERROR REPORT 7614187 ----------

I just clicked the Video Settings... Button.
Why is this happening?

Please tell me why.