From 'Some food are sweet' and 'Some food are sour', we cannot conclude all foods are either sweet or sour (other types may exist). We also cannot conclude some sweets are sour as the statements only relate food to sweet/sour, not sweet to sour directly. Neither conclusion follows.
Note: The chosen option 3 (Both I & II follow) is incorrect; the correct answer is option 4 (Neither I nor II follow).