What is the difference between a non-custodial and custodial interview?

What is the difference between a non-custodial and custodial interview?

• A. Non-custodial interviews require Miranda warnings if in custody.
• B. Custodial interviews are never subject to warnings.
• C. Non-custodial interviews occur when the subject is free to leave; custodial interviews require Miranda warnings if in custody.
• D. Custodial interviews are always conducted in private.

Answer: (C)