The not knowing if he was or he was n't . It was literally killing me ! Fortunately , a friend recommended a book to me that changed my life .
According to the above context, choose the best option to answer the following question.
Question: Why is the narrator so grateful to the friend ?
Options:
A. The friend has recommended them for a course .
B. The friend has recommended them for a loan .
C. The friend has recommended them a job .
D. The friend has recommended them a great book .


D