Evaluate students' ability to compare and critically assess WIMPs, axions, sterile neutrinos, and modified gravity as explanations for dark-matter phenomena by matching theoretical predictions to observational constraints (CMB, large-scale structure and Lyman-α forest, galaxy rotation curves and dwarf galaxy cores, gravitational lensing and cluster collisions, direct/indirect detection, and X‑ray lines), quantify parameter limits, and argue which observations most decisively discriminate among models.