Directions: The following question tests your ability to recognise grammar and usage errors. The sentence contains either a single error or no error at all. The error, if there is one, is underlined and lettered. If the sentence contains an error, select the one underlined part that must be changed to make the sentence correct. If the sentence is correct, select choice (E). In choosing your answer, follow the requirements of standard written English.

The better plan, however, is to (A) so educate and enlighten old and young (B) about the important subjects of health, (C) so that the necessity to (D) call a physician may occur less frequently. (E) No error