Assess students' ability to evaluate competing dark matter hypotheses—WIMPs, axions, MACHOs, and modified gravity—by comparing theoretical motivation, predicted astrophysical signatures (rotation curves, gravitational lensing, CMB, structure formation, Bullet Cluster), and experimental/observational constraints (microlensing, direct/indirect detection, axion haloscopes, cosmological probes). Include interpretation of parameter-space limits and proposals for discriminating tests.