A Tris buffer at pH 6.0 (here "Tris" is a nickname use for Tris hydroxymethyl amino methane). For the given pK_A table is Tris a compound you would select for a buffer at pH 6.0? Define this carefully that why this is or is not.

When this is not a chemistry you'd select for this buffer, then recommend alternative chemistry and also justify your selection.

Tris is not perfect for a buffer at given pH, when its pKa is more than 2 pH units away by 6.0. Therefore, at pH 6.0, Tris would be >90 percent protonated, and would be a lousy buffer in opposition to added acid. Both MES (2-(N-morpholino)ethanesulfonic acid) and carbonic acid have pKas near pH 6.0 and would therefore be better choices.