Correct Answer - 4
In water, no common ion effect will act hence `S_(1)` will be maximum .
`{:([CaBr_(2)]=0.01,,,[Br^(-)]=0.02,,),([NaBr]=0.01,,,[Br^(-)]0.01,,),([AgNO_(3)]=0.05,,,[Ag^(+)]=0.05,,):}`
More the concentration of common ion, less will be the solubility. `S_(1)gtS_(3)gtS_(2)gtS_(4)`