What Was the Main Reason for the Transition from the ICD-9

What was the main reason for the transition from the ICD-9 coding system to the ICD-10 coding system?

A) The ICD-10 coding system adds more numbers for billing.
B) The ICD-10 coding system provides a higher number to be used for functional outcomes.
C) The ICD-10 coding system provides specificity to delineate functional outcomes.
D) The ICD-10 coding system is no different from the ICD-9 coding system, just a higher number.