In evaluating NLP systems, as discussed in NVIDIA's Generative AI and LLMs course, validity and reliability are critical for selecting evaluation metrics. Validity ensures that a metric accurately measures the intended property (e.g., BLEU for translation quality or F1-score for classification performance), reflecting the system's true capability. Reliability ensures that the metric produces consistent results across repeated measurements under similar conditions, indicating stability and robustness. Together, these ensure trustworthy evaluations. Option A is incorrect, as validity is not about predicting trends, and reliability is not about data source integration. Option C is wrong, as validity and reliability are not primarily about computational cost or platform applicability. Option D is inaccurate, as validity and reliability do not focus on computation speed or high-volume processing. The course notes: "Validity ensures NLP evaluation metrics accurately measure the intended property, while reliability ensures consistent results across repeated evaluations, critical for robust system assessment." References: NVIDIA Building Transformer-Based Natural Language Processing Applications course; NVIDIA Introduction to Transformer-Based Natural Language Processing.