Deep learning models learn high-dimensional, non-linear representations through layered parameterization that resists simple causal narratives. The internal mechanisms (e.g., distributed feature representations and complex statistical transformations) are difficult to map to human-interpretable rules, making explanation challenging. This is the primary reason for explainability difficulty in deep learning.
Option A addresses data origin/volatility, not explainability. Option B mischaracterizes model behavior as mutable "knowledge" without logs. Option C notes probabilistic foundations but that alone does not make systems inexplicable.
References: AI Security Management (AAISM) Body of Knowledge: "Explainability and Interpretability- Complexity in Deep Learning," "Model Behavior, Surrogates, and Post-hoc Explanations"; AAISM Study Guide: "Interpreting High-Dimensional Representations," "Limits of Transparency in Neural Architectures."