When my wife and I lived in Texas, one morning, we were（1）our way home and decided to stop at a local gas station to get some breakfast. We noticed a man standing in front of the store. We could tell that he was a（2）man, because his clothes were dirty and worn. It looked like he had gone in to get（3）warm to drink but came out with nothing.（4）he must have not had enough money.
Then we saw a dog walk up to the front of the store. It was a（5）dog - we could tell that it had been feeding puppies. She was terribly in need of something to eat. There were people（6）by and not even taking a look at her. She might not have been as（7）and clean as most, but she still deserved better. We still did not do anything, but someone did. The guy, who did not buy himself anything to eat, went back into the（8）, bought a can of dog food and fed that dog.
I know that this story isn't as inspirational as most stories, but it（9）a great part in our lives. You see, that was Mother's Day weekend. A lot of people forget that some animals are（10）too. It took a straggler (流浪汉) to show me what I should have done. He made me a better man that day.
（1）下列正确的是（ ）

A.at

B.on

C.in

D.for