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: Pharmacology
Which of the following antimalarial has immunomodulatory effect? 
Select and explain. 
A. Hydroxychloroquine, B. Chloroquine, C. Quinine, D. All of the above
A: Hydroxychloroquine
Answer: A: Hydroxychloroquine 
Explanation: Hydroxychloroquine is an antimalarial agent with immunosuppressant propeies. It is thought to suppress intracellular antigen processing and loading of peptides onto MHC class II molecules by increasing the pH of lysosomal and endosomal compaments, thereby decreasing T-cell activation. Ref: Katzung 11th edition, Chapter 61.