Directions: The given sentence has been divided into four parts, one of which may contain an error. No sentence contains more than one error. If the sentence contains an error, select the underlined part that must be changed to make the sentence correct. If the sentence is correct, select choice 5 as the answer.

The purpose of grammatical links is to introduce students (1) to a select list of sources that they will find Immensely (2) interesting and useful in their grammar study, (3) especially those who (4) confuse between the noun and verb forms. (5) No error