For the 17 years my life was very happy. Then the first sad thing happened. My mother became very ill, and soon she knew that she was dying. Just before she died, she asked Elizabeth and me to go to her room. She held our hands and said, "Victor and Elizabeth, my children, I'm very happy because you love each other, and because one day you'll get married. Everyone in the family loves you, Elizabeth. Will you take my place in the family, my dear? I can die happy if you look after them when I have gone." My mother died and we were very sad, because we loved her dearly. Elizabeth was brave and helped us; her sweet smile gave us some happiness in the unhappy days after my mother's death. The time came for me to go to university. I didn't want to leave my sad family, but we all knew that I should go. It was hard to leave, too, because the parents of my good friend Henry would not let him go to university with me. So I had gone alone. On my first day at university I met my teacher, Professor Waldman, who was one of the greatest scientists in the world. He gave a wonderful talk to all the students who were starting at the university. He ended his talk by saying, "Some of you will become the greatest scientists of tomorrow. You must study hard and discover everything that you can. This is why God made you intelligent--to help other people." After the professor's talk, I thought very carefully. I remembered the storm when I was 15; I remembered how the lightning had destroyed the tree. From then on, I wanted to use electricity to help people, and I wanted to discover the secrets of life. I decided to work on these two things. I started to work the next day. I worked very hard and soon Professor Waldman and I realized that I could learn to be a very good scientist. The professor helped me very much, and other important scientists who were his friends helped me, too. I was interested in my work and I did not take one day's holiday during the next two years, I did not go home, and my letters to my family were very short. After two years, I had discovered many things and I built a scientific machine that was the best in the university. My machine would help me answer the most important question of all. How does life begin? Is it possible to put life into dead things? To answer these questions about life I had to learn first about death. I had to watch bodies from the moment when they died and the warm life left them. In the hospital and in the university, I watched the dying and the dead. Day after day, month after month, I followed death, so it was a dark and terrible time. I built a tall mast about 150 meters high, which is higher than the tallest building in the city, to catch lightning and send the electricity down to my machine in the lab. I believed I could use that electricity to give life to things that were dead. Then one day, the answer came to me. Suddenly I was sure that I knew the secret of life. According to the author, the secret of life is to  _  .
give life to things that were dead use electricity to help others build the best machine to learn about death become the greatest scientist of tomorrow
Question: For the 17 years my life was very happy. Then the first sad thing happened. My mother became very ill, and soon she knew that she was dying. Just before she died, she asked Elizabeth and me to go to her room. She held our hands and said, "Victor and Elizabeth, my children, I'm very happy because you love each other, and because one day you'll get married. Everyone in the family loves you, Elizabeth. Will you take my place in the family, my dear? I can die happy if you look after them when I have gone." My mother died and we were very sad, because we loved her dearly. Elizabeth was brave and helped us; her sweet smile gave us some happiness in the unhappy days after my mother's death. The time came for me to go to university. I didn't want to leave my sad family, but we all knew that I should go. It was hard to leave, too, because the parents of my good friend Henry would not let him go to university with me. So I had gone alone. On my first day at university I met my teacher, Professor Waldman, who was one of the greatest scientists in the world. He gave a wonderful talk to all the students who were starting at the university. He ended his talk by saying, "Some of you will become the greatest scientists of tomorrow. You must study hard and discover everything that you can. This is why God made you intelligent--to help other people." After the professor's talk, I thought very carefully. I remembered the storm when I was 15; I remembered how the lightning had destroyed the tree. From then on, I wanted to use electricity to help people, and I wanted to discover the secrets of life. I decided to work on these two things. I started to work the next day. I worked very hard and soon Professor Waldman and I realized that I could learn to be a very good scientist. The professor helped me very much, and other important scientists who were his friends helped me, too. I was interested in my work and I did not take one day's holiday during the next two years, I did not go home, and my letters to my family were very short. After two years, I had discovered many things and I built a scientific machine that was the best in the university. My machine would help me answer the most important question of all. How does life begin? Is it possible to put life into dead things? To answer these questions about life I had to learn first about death. I had to watch bodies from the moment when they died and the warm life left them. In the hospital and in the university, I watched the dying and the dead. Day after day, month after month, I followed death, so it was a dark and terrible time. I built a tall mast about 150 meters high, which is higher than the tallest building in the city, to catch lightning and send the electricity down to my machine in the lab. I believed I could use that electricity to give life to things that were dead. Then one day, the answer came to me. Suddenly I was sure that I knew the secret of life. According to the author, the secret of life is to  _  .
A. give life to things that were dead
B. use electricity to help others
C. build the best machine to learn about death
D. become the greatest scientist of tomorrow
Answer: