17. On the table are 0 - 9, these 10 number cards. Three people, A, B, and C, each take three of them, and sum all the different three-digit numbers that can be formed with the three number cards they have. The results for A, B, and C are $1554, 1688, 4662$, respectively. The remaining number card is (
）(Note: 6 or 9 cannot be flipped to become 9 or 6.)
【Analysis】If the three cards do not have 0, then the sum of the 6 three-digit numbers formed is $222 \times(a+b+c)$. If the three cards include 0, then only 4 three-digit numbers can be formed, with a sum of $211(a+b) \quad$, and $(222,211)=1$. Therefore, if the sum is a multiple of 222, there must be no 0, and if the sum is a multiple of 211, there must be a 0. Thus, the sum of the three cards for person A is $1554 \div 222=7$; the sum of the three cards for person B is $1688 \div 211=8$; the sum of the three cards for person C is $4662 \div 222=21$; the remaining card is $45-7-8-21=9$.