Q:Read the following article and select the best answer. Article: We have met the enemy, and he is ours. We bought him at a pet shop. When monkey-pox, a disease usually found in the African rain forest, suddenly turns up in children in the American Midwest, it's hard not to wonder if the disease that comes from foreign animals is homing in on human beings. "Most of the infections we think of as human infections started in other animals, " says Stephen Morse, director of the Center for Public Health Preparedness at Columbia University. It's not just that we're going to where the animals are, we're also bringing them closer to us. Popular foreign pets have brought a whole new disease to this country. A strange illness killed Isaksen's pets, and she now thinks that keeping foreign pets is a bad idea. "I don't think it's fair to have them as pets when we have such a limited knowledge of them," says Isaksen. "Laws allowing these animals to be brought in from deep forest areas without stricter control need changing," says Peter Schantz. Monkey-pox may be Researchers believe infected animals may infect their owners. We know very little about these new diseases. A new bug may be kind at first. But some strains may become harmful. Monkey-pox doesn't look a major infectious disease. But it is not impossible to pass the disease from person to person. Question: Why did Isaksen advise people not to have foreign pets? - They attack human beings. - We need to study native animals. - They can't live out of the rain forest. - We do not know much about them yet.
A:
We do not know much about them yet.