A、From the investigation by detectives. B、From the words of some witnesses. C、From the head of Hope Foundation. D、From the amoun

A healthy newborn girl was discovered in Central Park yesterday morning. The baby was abandoned on the top of a rock shortly before dawn after the mother gave birth to her there.
    The police said that the baby was healthy and weighed 7 pounds. Now they were searching for the mother. A policeman said that they had never had anything like this before. They really didn’t get babies left in the park.But they were just happy the baby was all right.
    The police rushed the baby to a nearby hospital. Fortunately she was OK. The police believed the baby was born less than half an hour before she was discovered. They also believed judging from the amount of blood found on the rock that the mother might have given birth there. It was 70 degrees when the baby was found.
    Detectives were investigating whether the mother was a homeless woman who called a baby rescue hotline early yesterday. The head of Hope Foundation said that his hotline received a call about 5:30 a.m. from a young homeless woman in Manhattan. The caller asked, "How do I get rid of my baby?" She was apparently in labor. Then she was told to go to either a hospital or a fire station. But the woman was afraid she would be recognized there. The head also said that the woman wouldn’t even tell him where he could possibly meet her since they had two teams that could help with the delivery, if necessary.
23. Why did the policemen feel happy?
24. How did the police know that the mother might have given birth on the rock?
25. Why did the woman refuse to go to a hospital or a fire station?