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Question 15 2 pts Which of the following is NOT a typical feature of a Preferred Provider Organization (PPO) plan? O To have the insurance cover a visit to a specialist, you typically need a referral from your primary care doctor O In-network services are covered at higher levels than out-of-network services PPO insurance plans generally offer more provider choices than Health Maintenance Organization (HMO) plans Out-of-network services are providers that are not considered preferred providers OPPO insurance plans with the same levels of coverage are generally more expensive than Health Maintenance Organization (HMO) plans