阅读下列短文，从每题所给的四个选项(A、B、C和D)中，选出最佳选项。
A
I am a taxi driver. One Monday morning, I had stopped at New York Hospital when I found a well-dressed man coming over. He was waving to me. I waited until he jumped into the cab. “La Guardia Airport, please,” he said.
As always, I wondered about my passenger. “What do you do?” “I am working at the hospital.” For some unknown reason, I decided to ask for his help.
“Could I ask a favor of you?” He didn’t answer. “I have a son, 16. He’s doing well in school. He wants a job this summer. Is there any possibility that you might get him a summer job?” After a minute, he said, “The medical students have a research project. Maybe he could fit in. Have him send me his school records.” He searched his pocket and handed me a card.
That evening, I pulled the card from my pocket. “Robbie,” I said proudly, “This could be a summer job for you. Send him your school records.” He read it out loud, “Fred Plum, New York Hospital.” “Is this a joke?” he said in doubt. After I shouted and threatened (恐吓) to cut off his pocket-money, Robbie promised to send off his grades the next morning.
Two weeks later, when I arrived home, my son handed me a letter from Plum. He was to phone Plum’s secretary for an interview.
Robbie got the job. The white coat he wore made him feel more important than he really was. As high school graduation neared, Plum was kind enough to write letters of recommendation (推荐) for universities. At last, Robbie was admitted to New York Medical College.
It never happened to me that a stranger should change my son’s future.
(b)、 
(d)、CH≡C-CH=CH2(p)的分子式均为C4H4。下列说法正确的是（ ）