题目内容：

Five years after a donor's bone marrow (骨髓)saved a pair of twin girls’ lives, the girls , Elizabeth and Kathryn ,from Minnesota got the chance to thank the man face to face.

The girls’ mother, Michele, said, “To think that somebody who didn’t know your children was selfless enough to give bone marrow to save them is amazing. They gave him giant hugs and danced the night away with him like they had known him before.”

The meeting came together thanks to Be the Match, a community of donors, volunteers, health care professionals and researchers.

The girl were born with a rare disorder that left them without any blood platelets(血小板).The bone marrow transplant was needed to change their DNA to avoid their organs shutting down.

Michele, her husband, and their son, tested negative when it came to being a match for the girls. They were put on the Be the Match list, which finally found Gruda.

“I become breathless,'' Michele said about finding a match. " because there are still so many things that could go wrong even though you have a donor."

Due to the uncertain result, the girls had to have their transplants done separately. Elizabeth’s was in 2011, and Kathryn’s was in 2012. The two girls also had to undergo chemotherapy(化疗).

The family was finally able to express their gratitude in person after Be the Match flew Gruda to Minnesota from Germany.

Gruda, who has three children of his own, tried to donate to a local girl in his town nearly 30 years ago but was not a match. Five years ago, he received a phone call that he was a match for the sisters and didn't hesitate to donate. His bone marrow was flown from Germany to use in the transplant.” “My three children rejoiced(高兴) that I came through as the best donor for the girls,'' he told Be the Match.

Both sisters are now completely healthy and 100 percent cured.

1.Why did Michele say “I become breathless” when I they found a match?

A. They hadn’t found a match till then.

B. They still feared something bad would happen.

C. All of their family members failed to pass the test.

D. The good news made them very excited.

2.Why did the girls have their transplants done separately?

A. Kathryn was then receiving chemotherapy.

B. Not all the bone marrow had arrived.

C. Because of the uncertain result.

D. The doctors were too busy to do two operations.

3.What do you know about Gruda?

A. He is always ready to donate his bone marrow.

B. He stayed at the twins home till the next day.

C. He has succeeded in helping two German patients.

D. He knew who his bone marrow was donated to well.

4.We can infer from the passage that the twins_____.

A. continue to undergo chemotherapy

B. went to Germany to thank Gruda.

C. go to hospital to get re-examined frequently.

D. have completely recovered from their disease