A、Water. B、Crops. C、Money. D、Trees. B由对话中提到的the farmers don’t have a real problem with the elephants until the elephants start e

M: So, what exactly are you doing to protect the elephants here?
W: Well, we have managed to raise a lot of money for this project. A lot of it is being used to compensate farmers for the damage that elephants do to their crops.
M: How does that protect the elephants?
W: Since the elephants cause damage to the crops, farmers are often tempted to go out and kill the elephants.
M: I see. So, the farmers don’t have a real problem with the elephants until the elephants start eating the crops. But why do the elephants do that?
W: Well, there aren’t enough trees to provide them with food on the land that has been reserved for them.
M: Mm. But if you successfully protect the elephants, their numbers will grow and they will need more food. That means that they’ll need more land.
W: That’s true, but we’ve solved that problem too. What we do is move some elephants to reservations where there are relatively few.
M: So that’s where you spend another large proportion of the money you raise.
W: Actually, it isn’t very expensive because we share the cost with the people who run the other reservations.
M: I see. How do you decide which elephants to move?
W: We use two criteria. The first is that we maintain the genetic diversity of the elephant herd. The second is that we transport the more aggressive members of the herd, which results in us spending less money compensating farmers.
M: Are there any plans to expand the reservation?
W: We have allocated some money to land purchases, but such purchases could have a damaging effect on the local human population, so we rarely do it.
M: What kinds of research are you doing on the elephants here?
W: We’re mainly studying the way that elephants interact with each other within a herd.
M: I see. Well, thanks very much for your time.
W: My pleasure.
Questions 23 to 25 are based on the conversation you have just heard.
23. Which of the following is the main source of conflict between the elephants and the local people?
24. Why is expanding the reservation not a realistic option?
25. Who are the speakers most likely to be?