A、A blood transfusion. B、An allergy test. C、A urine test. D、A biopsy. B通过对话内容可知，为了排除后续的食物过敏(food allergy)的问题，还需要做化验。因此本题答案为B。

W: Hi, Patrick, how are you feeling today?
M: A bit better.
W: That’s good to hear. Are you still feeling nauseas?
M: No. I haven’t felt sick to my stomach since you switched my medication.
W: Great, say, your test result came this morning.
M: It’s about time. Is it good news or bad?
W: I guess it’s a bit of both. Which do you want first?
M: Let’s get the bad news over with.
W: OK. It looks like you are going to need surgery to remove your tumor from your leg. After the operation you’re going to have to stay off your feet for at least 3 weeks. That means no soccer.
M: Well, I was afraid you were going to say that.
W: Now, for the good news. The biopsy shows the tumor is benign which means it is not cancerous. We’re going to take it out anyway, just to be on the safe side.
M: Wow, that’s a load off my mind. Thanks, doctor.
W: Don’t get too excited. We still need to get to the bottom of all this way of loathing. . .
M: I probably have just been so worried about stupid lump.
W: These things often are stress-related, but we’re still going to do a few blood tests just to rule a few things out.
M: Things like what? Cancer?
W: Actually, I am thinking more along the line of food allergy.
Questions 16-20 are based on the conversation you have just heard.
16. What did the man have to switch medication?
17. What is the bad news for the man?
18. What medical procedures has the man already undergone?
19. Why does the doctor ask the man to take a few blood tests?
20. Which of the following can best describe the man’s feeling in the end?