you read about pre-authorization and were asked quiz/exam questions about it, but what does this process actually entail

[answerhappygod]

you read about pre-authorization and were asked quiz/exam
questions about it, but what does this process actually entail?
What are the consequences if pre-authorization is not
performed/completed?
How do you think pre-authorization is actually performed in this
"internet" age?
Why is pre-authorization so important and what information needs
to be made available and provided to insurance companies (or their
third party processors) to make this process a success?
Why is accuracy and relevance of ICD10 and CPT codes so
important?