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: Unknown
Test discovered by this scientist is a type of 
Select and explain. 
A. Slide agglutination test, B. Tube agglutination test, C. CFT, D. Ring precipitation test
B: Tube agglutination test
Answer: B: Tube agglutination test 
Explanation: WIDAL Fernand Isidore discovered widal test.