4883C is the identity form my husband and my niece got one last year. It is important to have the current year and previous year tax return. They verify name, address, and ssn. They ask different questions my niece was asked things that pertained to her tax returns. My husband was asked what was his mother's maiden name and what job he currently works at things like that and one or two tax return questions.. It is not that bad so don't stress. I know getting a letter is scary but it was only a couple minutes and thats it. My husband received his tax return 6 weeks later and my niece got hers a week later. It really depends. Best of luck to everyone.
