Felix is joining a book club. The club members have already read 6 books together so far. Once Felix joins, they will read one new book each week. The equation representing the relationship between b, the total number of books and
w, the number of weeks, is b=w+6.
Which statement about this relationship is NOT true?

A. the number of weeks and total number of books increase together at a constant rate.
B. as the number of weeks increases by 1,the total number of books increases by 1.
C. the common difference between the number of weeks and total number of books is 6.
D. doubling the number of weeks also doubles the total number of books.