The Following Compounds Are Available as 0 Which Two Solutions Could Be Used to Prepare a Buffer

Short Answer

The following compounds are available as 0.10 M aqueous solutions. $$\begin{array} { | l | l | l | } \hline \text { A) pyridine } & \text { B) } \mathrm { LiClO } _ { 4 } & \text { C) } \mathrm { HClO } _ { 4 } \\\hline \text { D) } \mathrm { HClO } _ { 2 } & \text { E) } \mathrm { NaOH } & \text { F) phenol } \\\hline \text { G) triethylamine } & \text { H) } \mathrm { HClO } & \text { I) } \mathrm { NH } _ { 3 } \\\hline\end{array}$$
Which two solutions could be used to prepare a buffer with a pH of ~ 9? More than one answer may be possible.