Enantiomer
Step-by-step explanation:
The most likely reason for the given type of distinction is that the enzymes the body uses are typically stereospecific and only produce one enantiomer
Many of the enzymes used in the body are stereospecific - they will only react with one particular stereoisomer form of a molecule and will only catalyze a reaction that produces a particular isomer of the product
Often drugs are administered as a racemic mixture because work in the lab produces such a mixture even though only one of the isomers has any biological effect