Rome-Doctors and medical groups around the world last weekend reacted with strong opposition to the news that an Italian specialist is going in for cloning (克隆) the first human baby. Dr. Severino Antinori, who is the head of a hospital in Rome, has been referred to in an Arab newspaper as claiming that one of his patients is eight weeks pregnant (怀孕) with a cloned baby. Antinori refused to comment on the reports, but he said he hoped to produce a cloned embryo (卵) within two years. So far seven different kinds of mammals have already been successfully cloned, including sheep, cats and most recently rabbits. Professor Rudolf Jaenisch said: "I find it astonishing that people do this where the result can be foretold that it will not be a normal baby. It is using humans as guinea pigs. It makes people feel sick." But Ronald Green, director of a College in the US, said it is unlikely that an eight-week-old pregnancy would lead to a birth. So far all cloned animals have suffered from some different serious disorders, many of them dying soon after their births. From the passage, we can infer that ______.
A．humans have been cloned successfully B．so far all cloned animals died because of many diseases C．not all the cloned animals can survive D．doctors can clone humans within two years