Answer:
The most obsolete today was probably the second amendment because the second amendment states "A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed." However, today, in order to own a gun, you have to go through some kind of training or have a permit to legally own one. As a result, the second amendment is outdated because it says that people have the right to bear a gun and it doesn't say anything about having to have a permit or something like that.