Which of the following best defines the purpose of prefixes in expanding understanding of vocabulary?

The purpose of prefixes is fundamentally about modifying the meaning of root words. By attaching a prefix to a root word, it can change the word's original meaning or create a new meaning altogether. For instance, taking the word "happy" and adding the prefix "un-" results in "unhappy," altering the sentiment conveyed by the original word. This ability to modify meanings is crucial for students as they encounter new vocabulary, allowing them to deduce meanings of unfamiliar words by recognizing familiar roots and prefixes. This understanding enhances vocabulary comprehension and supports language acquisition, empowering students to interpret and use new words effectively in context.