When preprocessing text data for an LLM fine-tuning task, why is it critical to apply...

Subword tokenization, such as Byte-Pair Encoding (BPE) or WordPiece, is critical for preprocessing text data in LLM fine-tuning because it breaks words into smaller units (subwords), enabling the model to handle rare or out-of-vocabulary (OOV) words effectively. NVIDIA’s NeMo documentation on tokenization explains that subword tokenization creates a vocabulary of frequent subword units, allowing the model to represent unseen words by combining known subwords (e.g., “unseen” as “un” + “##seen”). This improves generalization compared to word-based tokenization, which struggles with OOV words. Option A is incorrect, as tokenization does not eliminate embeddings. Option B is false, as vocabulary size is not fixed but optimized. Option D is wrong, as punctuation handling is a separate preprocessing step.