Answer
The IUPAC name of the compound is $3-amino-2-hydroxybutanoic \hspace1mm acid$
Work Step by Step
The acid has 4 carbon atoms in its longest carbon chain containing the carboxylic functional group. It has a $amino$ substituent at position 3, and a $hydroxy$ substituent at position 2. So, the IUPAC name of the compound is $3-amino-2-hydroxybutanoic \hspace1mm acid$