Which of the following best describes the process of inflection?

The process of inflection refers to modifying a word to fit grammatical context, which is exactly what the correct answer conveys. Inflection typically involves adjusting the form of a word to indicate various grammatical features such as tense, mood, person, number, or case. For example, adding -s to a noun to indicate plurality (e.g., "cat" becomes "cats") or modifying a verb form to denote a different tense (e.g., "walk" becomes "walking" or "walked") are instances of inflection. This allows the word to align with the sentence structure and convey the intended meaning within a specific context.

Other options are based on different linguistic processes. Changing a word's meaning entirely pertains more to derivation, which creates a completely new word from a base word. Developing new words through compound formation involves combining two or more words to make a new word, while creating synonyms by altering sounds refers to phonetic changes that do not fit the grammatical modifications that inflection entails. Hence, the choice that highlights modification for grammatical purposes best encapsulates what inflection involves.