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。
I never thought I would have a life-changing experience a 
t Wal-Mart.
Although my thoughts were only on speed, the checkout line I was standing in wasn't moving as quickly as I wanted, and I glanced toward the cashier.
There stood a man in his seventies, wearing glasses and a nice smile. I thought, well, he's an old guy!
For the next few minutes I watched him. He greeted every customer before scanning the items. Sure, his words were the usual, “How' 
s it going? ”. But he did something different—he actually listened to people. Then he would respond to what they had said and engage them in brief conversations.
I thought it was odd. I has grown accustomed to people asking me how I was doing simply out of a robotic conversational habit. After a while, you don't give any thought to the question and just mumble something back. I could say, “I just found out I have six months to live, ”and someone would reply, “Have a great day! ”
But that wasn't the end.
He gave them the change, walked around the counter, and extended his right hand in an act of friendship. He looked the customers in the eyes. “I sure want to thank you for shopping here today, ”he told them. “You have a great day. Bye-bye. ”
The looks on the faces of the customers were priceless. There were smiles and some sheepish grins. All had been touched by his simple gesture—and in a place they never expected. They would gather their things and walk out, smiling.
Of course, he did the same to me and I got to know his name, Marty.
Who was that guy? It was as if Sam Walton had come back from the dead and invaded this old guy's body.
I had never walked away from that shop feeling like that.
