阅读下面短文，掌握其大意，然后从各题所给的四个选项（A、B、C和D）中，选出最佳选项。
Every fast-food employee knows that the drive-through window is the worst position. The window sticks with constant ice; the roar of engines hurts your ________; your words are lost in the howling wind.
On a ________ afternoon, everything changed.
Every once in a while, the sub-zero temperatures seal a ________ windows shut. Drivers don’t exactly enjoy having to stand outside in the cold, ________ their orders into a speaker box, when they expect to drive through on their heated leather seats. In such cases, most customers tend to show their annoyance to the employees.
This woman was ________.
“I’ll get the next car’s ________ as well,” she said as she came up to the window to pay. She stood outside, ________ much snow on her hair. Though she was obviously freezing, her bright ________ lit up her face like a fire.
“You can’t ________ their drinks,” I said, confused and tired.
“No, but I’ll buy them,” she said. “Pay it forward and all that.”
Completely puzzled, I charged her as ________, and when the next customer arrived at the window I explained what had just happened. I watched as his ________ changed — first angry to be out in the cold, then ________ at the random act of kindness, and finally, delighted by his ________.
“I suppose I’ll pay for the next order then,” he replied, nodding and waving at the impatient driver ________ him. He ________ over the cash and received his pre-paid hot drink. The trend continued. Customers arrived annoyed, only to leave ________ and pleased. Some were shocked to spend much more than they had expected, ________ others ended up receiving their order for less than half the price.
Five vehicles passed, then ten, then twenty. No one refused to pay. Customers stood at my window ________ a fist-full of change to buy drinks for a complete stranger. Cars drove off, honking (鸣笛) and ________ their thanks.
It only takes one customer, one person, to change the entire ________ of traffic. It only takes one moment, one smile, to warm up even the coldest of days.
1.A. earsB. handsC. feetD. back
2.A. freezingB. sunnyC. warmD. usual
3.A. truck’sB. vehicle’sC. car’sD. lorry’s
4.A. offeringB. throwingC. screamingD. cancelling
5.A. politeB. angryC. popularD. different
6.A. numberB. coffeeC. feeD. order
7.A. coveringB. increasingC. gatheringD. falling
8.A. eyesB. smileC. hairD. annoyance
9.A. payB. takeC. buyD. bring
10.A. instructedB. requestedC. directedD. suggested
11.A. gestureB. expressionC. figureD. feeling
12.A. inspiredB. upsetC. surprisedD. disappointed
13.A. turnB. senseC. deedD. luck
14.A. beyondB. beforeC. besideD. behind
15.A. tookB. lookedC. handedD. thought
16.A. shyB. calmC. anxiousD. regretful
17.A. whileB. sinceC. asD. unless
18.A. makingB. emptyingC. lyingD. holding
19.A. explainingB. sendingC. introducingD. casting
20.A. jamB. rowC. flowD. line
1.It can be concluded from paragraph 1 that ________.