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: Physiology
Secretors are those who? 
Select and explain. 
A. Secrete enzymes in blood, B. Secrete immunoglobulin in intestine, C. Secrete blood group antigen in sweat/saliva, D. Secrete hormones in response to stress
C: Secrete blood group antigen in sweat/saliva
Answer: C: Secrete blood group antigen in sweat/saliva 
Explanation: Ans. is'c'i.e., Secrete blood group antigen in sweat/saliva