Identifying Functional Groups

Functional groups are specific groups of atoms within molecules that determine the characteristic chemical reactions of those molecules. Understanding functional groups is crucial for predicting the behavior of organic compounds. In organic chemistry, three functional groups frequently encountered are alcohols, aldehydes, and carboxylic acids. Consider the following molecule represented by its structure: C₃H₆O.
This compound contains an oxygen atom within its structure, but depending on how it is incorporated, it may exhibit different functional group characteristics. Which of the following functional groups is this compound most likely to represent?