完形填空：阅读下面短文，从短文后各题所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项。
Mrs. Hammond was old and blind, but she was determined to do everything for herself. She even used to go for walks by herself once a day for 1, and found her way by 2 things with her white stick. She learned where everything was, so she never lost her way.
One day, some men came and cut down some of the familiar trees at the side of one of the paths which she 3. When she reached that place that evening, she did not 4 the trees with her stick, so she was in 5.
She 6 for a while and listened, but did not 7 any other people, so she went for a kilometer or two, and then she heard 8 beneath her. “Am I 9? I suppose so,” she said, “I must be on a 10, and there must be a river under me. I've been told that there's a river in this part of the country, but I don't know its exact 11. How am I going to get 12 to my house from her e?”
All at once she heard a man's friendly 13 near her. “Excuse me, can I help you?”“How kind of you!” Mrs. Hammond answered. "Yes, please. Some of the trees which I follow have been 14 today, and if I hadn't been 15 enough to meet you, I don't know 16 I'd have done. Can you please 17 me to get home?”
“ Certainly,” the man answered. “Where do you live?”
Mrs. Hammond told him, and the man took her to her house . She told the man how pleased she was that she had met him. But the man said. “I want to 18 you.”
Mrs. Hammond asked, “Whatever for?”
“Well,” the man said quietly, “I was balanced (悬在) on the edge of that bridge for ages in the 19, because I was trying to make up my mind to 20 myself into the river and drown myself. But I'm not going to do it now.”
