This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
Glanzmann thrombasthenia is due to 
Select and explain. 
A. Decreased GpIb, B. Decreased GpIIb/IIa, C. Anti-GpIIb/IIIa antibodies, D. Inhibition or deficiency of ADAMTS 13
B: Decreased GpIIb/IIa
Answer: B: Decreased GpIIb/IIa 
Explanation: Glanzmann thrombasthenia is an autosomal recessive disorder. There is a failure of primary platelet aggregation with ADP or collagen due to inherited deficiency of two platelets membrane glycoproteins. It is caused due to deficiency of glycoprotein IIb- IIa.