This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Communicable Diseases, Subject name: Social & Preventive Medicine
Preservative added in DPT vaccine is : 
Select and explain. 
A. Zinc phosphate, B. Aluminum phosphate, C. MgS04, D. ZnS04
B: Aluminum phosphate
Answer: B: Aluminum phosphate 
Explanation: Ans. is 'b' i.e. Aluminium Phosphate Aluminium phosphate is used as an adsorbent in DPT vaccine. Adsorption increases the immunological effectiveness of the vaccine