题目内容：

    AIDS may be one of the most undesirable diseases in the world. Luckily, there is now hope for AIDS patients. According to a recent paper published in the New England Journal of Medicine, Chinese scientists have successfully used CRISPR technology-a method of gene editing-to treat a patient with HIV. While it may not have cured the patient fully, it still represents a huge step forward in fighting the disease.

The patient was a 27-year-old Chinese man who was diagnosed with both AIDS and acute lymphoblastic leukemia, a type of blood cancer. Despite his bleak situation, doctors offered him a glimmer of hope: a bone marrow (骨髓) transplant to treat his cancer and an experimental treatment for his HIV.

They edited the DNA in bone marrow stem cells from a donor before transplanting the cells into the patient. Specifically, the treatment involved using the gene-editing tool CRISPR-Cas9 to delete a gene known as CCRS, which encodes a protein that HIV uses to get inside human cells. Without the gene, HIV is unable to enter cells. Talking about the gene, lead scientist Deng Hongkui told CNN, “After being edited, the cells-and the blood cells they produce-have the ability to resist HIV infection.” Nineteen months after the treatment, the patient’s leukemia was in complete relief and donor cells without CCR5 remained, according to the research paper.

Though the transplant did not cure the man’s HIV, it still showed the effectiveness of gene-editing technology, as there was no indication of any unintended genetic alterations (改变) -a major concern with past gene therapy experiments.

Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security in the United States, who was not involved in the study, praised the treatment. “They did a very innovative experiment, it was safe,” he told Live Science. “It should be viewed as a success.”

Deng believes gene-editing technology could “bring a new dawn” to blood-related diseases such as AIDS and sickle cell anemia. Thanks to this new technology, “the goal of a functional cure for AIDS is getting closer and closer,” he said.

1.How did the new treatment fight against HIV?

A.By preventing HIV from entering cells. B.By changing the structure of HIV.

C.By removing a protein that HIV feeds on. D.By identifying and killing HIV.

2.What was the result of the treatment?

A.CCR5 and other genes in the patient’s cells were changed.

B.Some of the patient’s blood cells could resist HIV infection.

C.HIV could no longer get into the patient’s cells.

D.The donor cells without CCR5 disappeared finally.

3.What do we know about the experiment?

A.It has provided an innovative way to cure AIDS patients.

B.It pointed out the problems of gene therapy for AIDS.

C.It’s the first experiment to use gene-editing technology to treat AIDS.

D.It could offer a safe treatment for blood-related diseases.