Answer
The IUPAC name of the compound is $5,5-dimethyl-4-oxohexaanoic \hspace1mm acid$
Work Step by Step
The acid has 6 carbon atoms in its longest carbon chain containing the carboxylic functional group. It has 2 $methyl$ substituent at position 5, and an $oxo$ substituent at position 4. So, the IUPAC name of the compound is $5,5-dimethyl-4-oxohexaanoic \hspace1mm acid$
