What field of study does lexicology focus on?

Lexicology is specifically concerned with the study of words and vocabulary. This field explores the nature, meaning, and function of words, examining their origins, relationships, and uses within a language. By focusing on vocabulary, lexicology helps to understand how words convey meaning and how they can change over time, reflecting cultural and social influences.

In contrast, the other options pertain to different aspects of language study. For instance, grammar rules relate to the structure and system that governs how words are combined to form sentences, while the analysis of sentence structure looks at how sentences are organized and constructed. The development of new words, while related to lexicology, is more specifically a part of a broader field known as neology. Therefore, the primary focus of lexicology remains on words and vocabulary itself, making this choice the most accurate representation of the field.