Either will do

[screenactorsguild]

Here is a sentence from my homework at school:
" Would you like to have beer or orange juice? Any will do (correct the mistake)
Any => Either (in my teacher's opinion)
From my point of view, any => anything
Of course my teacher was right, but I couldn't know why?

 

[Giorgio Spizzi]

The sentence is an offer of one or the other of TWO drinks. In these cases EITHER (ONE) is used. ANY, on the other hand, would be appropriate in case more than two (drinks, etc.) had been offered.

GS