Final answer:
The information provided does not answer the question about the ANA membership size; it reflects the demand and supply of nurses in a specific region and cannot be used to determine the ANA membership. Accurate membership numbers should be obtained from the official ANA resources.
Step-by-step explanation:
The student's question concerns the membership size of the American Nurses Association (ANA), which is a professional organization representing the interests of registered nurses (RNs) in the United States. Based on the choices given of approximately 3 million, 1 million, 500,000, and 300,000, it appears there may be some confusion as the data provided does not directly answer the question about the ANA's membership. Instead, the data reflects the demand and supply of nurses in a specific region, Minneapolis-St. Paul-Bloomington, which cannot be used to infer the total number of ANA members.
Therefore, without current and specific data on the ANA's membership, the accurate number of nurses belonging to the ANA cannot be deduced from the information provided. It would be recommended to consult the official ANA website or their annual reports for the most accurate and recent figures on membership.