A mobile number consists of ten digits. First four digits are 9, 9, 9 and 9. The last three digits are 7, 8 and 9. The remaining digits are distinct and make the mobile number the greatest possible number. Find these digits.

A mobile number consists of ten digits. First four digits are 9, 9, 9

1.	A mobile number consists of ten digits. First four digits are 9, 9, 9 and 9. The last three digits are 7, 8 and 9. The remaining digits are distinct and make the mobile number the greatest possible number. Find these digits.
A.	6, 5, 4
B.	6, 5, 0
C.	6, 5, 7
D.	5, 6, 4
E.	None of these
Answer» B. 6, 5, 0