Final answer:
Prothrombin time is a good screening test for rodenticide ingestion as it measures the time it takes for blood to clot.
Step-by-step explanation:
The coagulation assay that is a good screening test for rodenticide ingestion is a. Prothrombin time.
This test measures the time it takes for blood to clot. In cases of rodenticide ingestion, certain substances in the rodenticide can interfere with the clotting process, resulting in prolonged prothrombin time.
By measuring prothrombin time, doctors can detect abnormalities in blood clotting that may indicate rodenticide ingestion.