# How can lysine and glycine be separated from each other?The isoelectric points are pH 9.6 for lysine and pH 5.97 for glycine

$\begin{array}{1 1}(a)\;\text{By changing pH of the solution}\\(b)\;\text{By changing temperature of the mixture}\\(c)\;\text{By steam distillation}\\(d)\;\text{By fractional distillation}\end{array}$

At pH 9.6 the solubility of lysine is minimum hence precipitated.
Hence (a) is the correct answer.