Read the following article and answer the question. Article: My friend Jennie gave her bone marrow( )to a 50-year-old woman, a woman she has never met. At the end of March, the Red Cross called back. Six different blood elements were tested ; Jennie matched five completely and was about a 3/4 match of the six. So she was the best match. In April, Jennie went for a complete physical exam by one of the doctors who would perform the surgery. The doctor had to make sure that it would be no tread to her. The doctor told her that the surgery would need to have two quarts of bone marrow from her hip bones. Jennie would probably be released the same day the surgery took place and should expect to be painful for a couple of months. "I didn't think it was that big a deal until I realized I was a match," Jennie said. "There was not a question in my head. It didn't seem like something that was going above and beyond. " Jennie was left with two very small scars on her lower back from the surgery and was giving medication to help reduce the pain. She still felt a great deal of pressure on her lower back. "Being only 21, I felt like I am not old enough to significantly impact someone's life," Jennie said. " It seems strange to me that I could possibly save this woman's life which was being cut short by cancer. " Three weeks after the surgery, Jennie received a car from the Red Cross representative who told her the transplant was successful. "I feel good, and I think it will actually work for her. " She said, "So many people say that they'd only donate if it was for a family member or close friend. This woman was someone's family and someone's friend. Obviously no one she knows is a match, and the fact that you'd be able to help a perfect stranger is greater. " Question: Jennie gave her bone marrow to _ . Answer:
Available choices:
[a]. a close friend
[b]. a stranger
[c]. a classmate
[d]. a
[b].