CPB (Certified Professional Biller) Certification Practice Exam

The insurance plan created in 1929 that guaranteed subscribers up to 21 days of hospitalization per year for an annual premium of $6 is Blue Cross. This program was designed to provide hospital service coverage and was one of the first pre-paid health insurance plans, setting a precedent for future health insurance models. Blue Cross specifically was focused on hospital care, which laid the groundwork for the development of other health insurance products later on.

While options such as the BlueCard Program and Blue Cross Blue Shield (BCBS) relate to the broader context of health insurance and the Blue Cross system, they were established later and incorporated more extensive services and networks. The original Blue Cross plan and its prominent role in the evolution of health insurance make it the correct choice for this question.