Final answer:
The PPO model provides the highest degree of flexibility for patients, allowing them to visit any healthcare provider without a referral and including those outside their network at a higher cost. The correct option is (B).
Step-by-step explanation:
The health insurance model that offers the most flexibility for patients is the Preferred Provider Organization (PPO).
In contrast to Health Maintenance Organizations (HMOs), PPOs allow patients to see any healthcare provider they wish without a referral, including those outside their network, though at a potentially higher cost.
PPO plans generally offer more freedom in terms of choices of doctors and hospitals.
The other models mentioned, such as HMO, Exclusive Provider Organization (EPO), and Point of Service (POS), often have more restrictions on which healthcare providers and facilities patients can use, or they may require a referral from a primary care doctor before consulting a specialist.