Read each sentence to find out whether there is any grammatical error in it. The error, if any will be in one part of the sentence. The letter of that part is the answer. If there is no error, the answer is 'E'. (Ignore the errors of punctuation, if any).
Both the brothers are so good-natured that they look at their old and aged parents very well.
Both the brothers are
so good-natured that
they look at their
old and aged parents very well.
No error
Correct answer is C
they look after their