A、You have to pay a lot for it. B、You may not get your money back immediately. C、You may not get help immediately. D、You have to

Obtaining good health insurance is a real necessity while you are studying overseas. It protects you from minor and major medical expenses that can wipe out not only your savings but your dreams of an education abroad. (16)There are often two different types of health insurance you can consider buying: international travel insurance and student insurance in the country where you will be going. An international travel insurance policy is usually purchased in your home country before you go abroad. It generally covers a wide variety of medical services and you are often given a list of doctors who may even speak your native language in the area where you will travel. (17)The drawback might be that you may not get your money back immediately, in other words, you may have to pay all your medical expenses and then later submit your receipts to the insurance company. On the other hand, getting student health insurance in the country where you will study might allow you to only pay a certain percentage of the medical cost at the time of service and thus you don’t have to have sufficient cash to pay the entire bill at once. Whatever you decide, (18)obtaining some form of health insurance is something you should consider before you go overseas. You shouldn’t wait until you are sick with major medical bills to pay off.
Questions 16 to 18 are based on the passage you have just heard.
16.What are the two types of health insurance mentioned in the passage?
17.What’s the drawback of the international travel insurance?
18.What does the speaker suggest doing before going overseas?