$32 \cdot 4$ To number the pages of a book, a printing worker used 3289 digits. Then the number of pages in the book is 
(A) 1095.
(B) 1096.
(C) 1097.
(D) None of the above.
(China Shanghai Junior High School Mathematics Competition, 1987)
［Solution］Note the following facts:
$1 \sim 9$ pages use 9 digits in total;
$10 \sim 99$ pages use $2 \cdot 90=180$ digits in total;
$100 \sim 999$ pages use $3 \cdot 900=2700$ digits in total;
In total, $9+180+2700=2889$ digits.
Thus, there are $3289-2889=400$ digits left, which can form 100 four-digit numbers, i.e., $1000 \sim 1099$.
Therefore, the answer is $(D)$.