Polylactic acid (PLA) is a widely used biodegradable thermoplastic polyester derived from renewable agricultural resources like corn starch. Its polymer repeating unit is shown below:
What is the systematic IUPAC name of the monomer unit from which PLA is polymerised?
3-hydroxypropanoic acid3\text{-hydroxypropanoic acid}3-hydroxypropanoic acid
2-hydroxypropanoic acid2\text{-hydroxypropanoic acid}2-hydroxypropanoic acid
3-hydroxybutanoic acid3\text{-hydroxybutanoic acid}3-hydroxybutanoic acid
2-hydroxybutanoic acid2\text{-hydroxybutanoic acid}2-hydroxybutanoic acid