NameError when using input in python

I am trying to get user response using input method as given below.
res = input('What size drink can I get for you? \n[a] Small \n[b] Medium \n[c] Large \n> ')

When I try to print res, I get the error message NameError: name a is not defined.

Hello @arc9885118205, welcome to the forums! Can you post a screenshot of this, please?

Hey @arc9885118205 ,
If you enter something else which is not there in the current python context, then it will fail will the NameError. this will be evaluated as a function call expression by python and it will be executed. In python 3.