Could you please solve it clearly n let me know the answer for it with diagram

If we assume that those who answered that they like two drinks - i.e. milk and coffee, coffee and tea, etc. like atleast two beverages - i.e. they could either like the third beverage or or not, we can solve this as follows:

 

Those who like all the drinks - 10

Those who like milk and coffee only - 20 - 10 (those who like all of them) = 10

Those who like coffee and tea only = 30-10 = 20

Those who like milk and tea only - 25-10 - 15

Those who like milk alone = 12

Those who like coffee alone = 5

Those who like tea alone = 8

 

The sum of these numbers is 80. Therefore the students who drank none of the beverages is 100-80 = 20.