This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bleeding Disorders, Subject name: Pathology
Failure of clot retraction indicates 
Select and explain. 
A. Low platelet count, B. Factor VIII deficiency, C. Facto XIII deficiency, D. Fibrinogen deficiency
A: Low platelet count
Answer: A: Low platelet count 
Explanation: Ans. (a) Low platelet count(Ref: Robbins 9th/pg 657)This test measures the amount of time it takes for a blood clot to pull away from the walls of a test tube (Shrinking).The edges of the blood vessel wall at the point of injury are slowly brought together again to repair the damage.It is used to evaluate and manage blood platelet disorders, including Glanzmann's thrombastheniaSo Clot retraction depends primarily on the number and activity of the blood platelets