This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Paediatric Care in RCH: BW, BL, PEM, Breast Feeding, Subject name: Social & Preventive Medicine
Which of the following is known as 'the medical discovery of 20th century'? 
Select and explain. 
A. Zidovudine, B. Smallpox vaccine, C. ORS, D. Penicillin
C: ORS
Answer: C: ORS 
Explanation: Oral Rehydration Therapy (O), a cheap and effective way to tackle moality from diarrohea Hence, it is 'The medical discovery of the century' composition of Reduced Osmolarity ORS - Na+ 75 mmol /L K+ 20 mmol /L Cl- 65 mmol/L Citrate 10 mmol/L Glucose 75 mmol/L Total 245 mmol/L