Name two sources of bias that can affect the validity of rodent study outcomes and how to mitigate them.

• A. Seasonal bias and weather bias; mitigation unknown.
• B. Payment bias and ordering bias; mitigation with randomization.
• C. Age bias and sex bias; mitigation with bigger cages.
• D. Selection bias (randomization) and observer bias (blinding); mitigate via randomized allocation and blinded outcome assessment.

Answer: (D)