The arrival of corpus linguistics has revitalized

The correct option is: The Writing Of Observation-Based Grammar.

Step-by-step Explanation:

1. Understanding Corpus Linguistics: Corpus linguistics is the study of language based on "corpora" (plural of corpus), which are large, structured collections of real-world texts (both written and spoken). Rather than relying on theoretical assumptions or intuitive beliefs about how language *should* work, corpus linguistics analyzes actual database records of how people *actually* use language in real contexts.

2. What is Observation-Based Grammar? Traditionally, grammar rules were often prescriptive, dictated by authorities based on formal logic or classical traditions. With corpus linguistics, grammarians can observe millions of real-life examples to see which grammatical patterns are truly common, how they vary across contexts, and how they evolve. This practice of writing grammar rules based directly on empirical evidence and real-world linguistic data is known as "observation-based grammar."

3. Connecting the Concepts: Therefore, the advent and tools of corpus linguistics have directly revitalized the writing of observation-based grammar by providing the empirical evidence and computational power needed to observe, verify, and document real language patterns in systematic detail. It moves grammar writing away from intuition and toward data-driven observation.